Answer:
I believe the answer would be: D
an independent variable that is affected by the other
experimental variable
Correct me if im wrong
Explanation:
). In a titration, a student obtained an average titre value of 3.9 cm3 of 0.3 M HCl. If the volume of Na2CO3 solution used is 10 cm3 and the indicator used is phenolphthalein, calculate; (i). the molarity of the Na2CO3 (4 marks) (ii). the mass concentration of the Na2 theCO3. (4 marks)
Answer:
I) 0.0585 M
ii)6.2 g dm-3
Explanation:
The reaction equation is given as;
Na2CO3(aq) +2HCl(aq)------> 2NaCl(aq) + CO2(g) +H2O(l)
Concentration of acid CA= 0.3 M
Volume of acid VA= 3.9 cm^3
Concentration of base CB= the unknown
Volume of base VB= 10 cm^3
Number of moles of acid NA= 2
Number of moles of base NB= 1
From;
CAVA/CBVB= NA/NB
CAVANB=CBVBNA
CB= CAVANB/VBNA
substituting values;
CB= 0.3 × 3.9 × 1/ 10.0 × 2
CB= 0.0585 M
ii) mass concentration= molar concentration × molar mass
Molar mass of Na2CO3= 106 gmol-1
Mass concentration= 0.0585 × 106 = 6.2 g dm-3
Solution C is a 1.00 L buffer solution that is 1.420 M in acetic acid and 0.67 M in sodium acetate. Acetic acid has a pKa of 4.74. What is the pH change of this solution upon addition of 0.10100 mol of HCl? Enter a negative number to 3 decimal places.
Answer:
The correct answer is 0.10.
Explanation:
Based on the given question, in a buffer solution of 1 liter, the molarity of acetic acid is 1.420 M and the molarity of sodium acetate is 0.67. The pKa value of acetic acid given is 4.74, now the pH of buffer is,
pH of buffer = pKa + log ([CH3COONa]/[CH3COOH])
= 4.74 + log (0.67/1.420)
= 4.74 + (-0.326)
= 4.41
Now 0.10100 mol of HCl is added, the HCl reacts with sodium acetate to give,
CH3COONa + HCl = CH3COOH + NaCl
Now the concentration of CH3COONa becomes = 0.67-0.101 = 0.57 M, and the new concentration of CH3COOH becomes = 1.420 + 0.101 = 1.52 M
Now the new pH will be,
= pKa + log (0.57/1.52)
= 4.74 + (-0.426)
= 4.31
The pH change is 4.41-4.31 = 0.10
Potatoes can be peeled commercially by soaking them in a 3M to 6M solution of sodium hydroxide, then removing the skins by spraying them with water. If titration of 12.00 mL of the sodium hydroxide requires 30.6 mL of 1.65 M HCl solution, what is the concentration of NaOH used in potato peeling?
Answer:
4.21 M
Explanation:
Step 1: Write the balanced equation
NaOH + HCl ⇒ NaCl + H₂O
Step 2: Calculate the reacting moles of HCl
30.6 mL of 1.65 M HCl reacted. The reacting moles of HCl are:
[tex]0.0306 L \times \frac{1.65mol}{L} = 0.0505 mol[/tex]
Step 3: Calculate the reacting moles of NaOH
The molar ratio of NaOH to HCl is 1:1. The reacting moles of NaOH are 1/1 × 0.0505 mol = 0.0505 mol.
Step 4: Calculate the molar concentration of NaOH
0.0505 moles of NaOH are in 12.00 mL. The molar concentration of NaOH is:
[tex]M = \frac{0.0505 mol}{0.01200L} = 4.21 M[/tex]
Isomers of hydrocarbons have the same _______formula but different ____formula.
Answer:
Isomers of hydrocarbons have the molecular formula but structural formula.
Explanation:
Molecules with the same structural formula, but different molecular geometries (spatial arrangement) are called isomers. These differences in the arrangement of the various atoms confer certain differences in chemical properties to the resulting hydrocarbons, even though their chemical composition is the same. There are two types of isomers:
Structural isomers: Here, each atom are connected or bonded in different ways, hence structural isomers may contain different functional groups or pattern of bonding. structural isomers are further divided into: chain, position, and functional group isomers.
Stereoisomers: Here, the connections of the atoms are the same, but the difference is in their orientation in space
If you touch a hot stove, the nervous system works closely with which other organ system to help your body react by pulling away quickly
1 Skeletal System
2 Muscular System
3 Digestive System
4 Circulatory System
Answer:
2. Muscular System
Explanation:
The muscular system is associated with body motion. Hence, the right answer is option 2.
Select all the correct answers.
What are three disadvantages of making and using plastic?
a. it pollutes the land and water
b. it requires cutting down trees from raw materials
c. it takes an incredibly long time to break down
d. it freely conducts heat and electricity
f. it isn't easy to recycle
Answer:
it is either a or c because they make the most sense
A mixture of krypton and argon gases, at a total pressure of 733 mm Hg, contains 3.97 grams of krypton and 6.34 grams of argon. What is the partial pressure of each gas in the mixture?
Answer:
Partial pressure of krypton= 167.12 mmHg
Partial pressure of argon = 565.88 mmHg
Explanation:
The partial pressure of a gas in a mixture of gasses is equal to the total pressure multiplied (Pt) by the mole fraction of the gas (X):
P= X Pt
The total pressure is Pt= 733 mmHg
The mole fraction is given by the following:
X = number of moles of gas/ total number of moles
For krypton (Kr) , the molecular weight is 83.8 g/mol and we calculate the number of moles by dividing the mass into the molecular weight as follows:
moles of Kr = 3.97 g/(83.8 g/mol)= 0.047 moles
For argon (Ar), the molesular weight is 39.9 g/mol, so we calculate the number of moles as follows:
moles of Ar = 6.34 g/(39.9 g/mol)= 0.159
Now, we calculate the total number of moles (nt):
nt= moles of Kr + moles of Ar = 0.047 moles + 0.159 moles = 0.206 moles
The mole fraction of each gas is now calculated:
X(Kr)= moles of Kr/nt = 0.047 moles/0.206 = 0.228
X(Ar)= moles of Ar/nt = 0.159 moles/0.206 = 0.772
Finally, with the mole fractions and the total pressure we calculate the partial pressure of each gas as follows:
P(Kr) = X(Kr) x Pt = 0.228 x 733 mmHg= 167.12 mmHg
P(Ar) = X(Ar) x Pt = 0.772 x 733 mmHg= 565.88 mmHg
which option describes energy being released as heat?
A- a Child shivering in the cold
B- Lions Sleeping after a big meal
C- A surfer on a Surfboard
D- A Baby Bird eating a Worm
Answer:
a
Explanation:
A child shivering gives off energy to transfer that energy into heat
Answer:
A
Explanation:
What is the symbol for the chlorine ion that forms when chlorine nonmetal reacts with sodium? A. C +1 B. Cl -1 C. Cl+1 D. C -1
Answer:
B. Cl -1
Explanation:
Chlorine has 7 valence electrons and needs one more to complete its octet thus takes one electron from sodium to become negatively charged Cl^-1.
In the reaction of silver nitrate and sodium chloride to produce solid silver chloride, sodium ions and nitrate ions are ________. spectator ions gases solvents liquids molecules
Answer: spectator ions
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Spectator ions are defined as the ions which does not get involved in a chemical equation or they are ions which are found on both the sides of the chemical reaction present in ionic form.
The total ionic chemical equation is:
[tex]Ag^+(aq)+NO_3^-(aq)+Na^+(aq)+Cl^-(aq)\rightarrow AgCl+Na^+(aq)+NO_3^-(aq)[/tex]
The ions which are present on both the sides of the equation are sodium and nitrate ions which are called as spectator ions and hence are not involved in net ionic equation.
A ground state hydrogen atom absorbs a photon of light having a wavelength of 92.57 nm. It then gives off a photon having a wavelength of 954.3 nm. What is the final state of the hydrogen atom? Values for physical constants can be found in g
Answer:
the final state of the hydrogen atom = 3
Explanation:
From the given information;
Let first calculate the amount of energy by the ground state atom during the atoms absorbs photon light by using the formula:
[tex]E_{absorbs} = \dfrac{hc}{\lambda}[/tex]
where;
h = planck's constant = [tex]6.626*10^{-34 }\ \ Js[/tex]
c = speed of light = [tex]3.0*10^8 \ \ m/s[/tex]
λ = wavelength = 92.57 nm = 92.57 × 10⁻⁹ m
[tex]E_{absorbs} = \dfrac{6.626*10^{-34 }\ \ Js * 3.0*10^8 \ \ m/s}{92.57*10^{-9} \ \ m}[/tex]
[tex]E_{absorbs} = 2.15 *10^{-18} \ J[/tex]
The energy emitted by the hydrogen atom is calculated by using the same formula from above ; but here , the wavelength λ = 954.3 nm = 954.3 × 10⁻⁹ m
[tex]E_{absorbs} = \dfrac{6.626*10^{-34 }\ \ Js * 3.0*10^8 \ \ m/s}{954.3*10^{-9} \ \ m}[/tex]
[tex]E_{absorbs} = 2.08 *10^{-19} \ J[/tex]
The change in the energy absorbed is:
[tex]\Delta E= 2.15 *10^{-18} \ J - 2.08 *10^{-19} \ J[/tex]
[tex]\Delta E= 1.94 *10^{-18} \ J[/tex]
The final state of the atom can be determined by using the relation:
[tex]\Delta E = R_H [\dfrac{1}{1^2}-\dfrac{1}{n^2_f}][/tex]
where;
[tex]R_H[/tex] = Rydberg constant = 2.18 × 10⁻¹⁸ J
[tex]\dfrac{\Delta E}{R_H} = [\dfrac{1}{1^2}-\dfrac{1}{n^2_f}] \\ \\ \\ \dfrac{1.94*10^{-18} \ J}{2.18*10^{-18} \ J } = [\dfrac{1}{1^2}-\dfrac{1}{n^2_f}] \\ \\ \\ 0.889 = [\dfrac{1}{1^2}-\dfrac{1}{n^2_f}] \\ \\ \\ 1 - 0.889 = \dfrac{1}{n^2_f} \\ \\ \\ 0.111= \dfrac{1}{n^2_f} \\ \\ \\ {n^2_f} = \dfrac{1}{0.111} \\ \\ \\ {n^2_f} = 9 \\ \\ \\ {n_f} = \sqrt{9} \\ \\ \\ \mathbf{n_f = 3}[/tex]
Thus; the final state of the hydrogen atom = 3
[tex]E_a_b_s_o_r_b_e_d = (6.626 * 10^-^3^4 J.s) * (3.00 * 10^8 m/s) / (92.57 *10^-^9 m)[/tex]We can use the fact that the energy of the photon is given by the equation: to determine the final position of the hydrogen atom.
E = hc / λ
Where:
E is the energy of the photon,
h is Planck's constant [tex](6.626 * 10^-^3^4 J.s)[/tex],
c is the speed of light in a vacuum [tex](3.00 * 10^8 m/s)[/tex], and
λ is the wavelength of the photon.
Let's first determine the energy of the absorbed photon:
[tex]E_a_b_s_o_r_b_e_d = hc /[/tex]λ[tex]_a_b_s_o_r_b_e_d[/tex]
[tex]E_a_b_s_o_r_b_e_d = (6.626 * 10^-^3^4 J.s) * (3.00 * 10^8 m/s) / (92.57 *10^-^9 m)[/tex]
The energy of the photon released will then be determined by:
[tex]E_e_m_i_t_t_e_d = hc[/tex] / λ[tex]_e_m_i_t_t_e_d[/tex]
E[tex]_e_m_i_t_t_e_d[/tex] = [tex](6.626 * 10^-^3^4 J.s) * (3.00 * 10^8 m/s) / (945.3 *10^-^9 m)[/tex]
The energy difference between the absorbed and released photons must now be determined:
ΔE = [tex]E_e_m_i_t_t_e_d - E_a_b_s_o_r_b_e_d[/tex]
The energy levels of hydrogen are given by the equation:
ΔE = -13.6 eV *[tex](1 / n^2_f_i_n_a_l - 1 / n^2_i_n_i_t_i_a_l)[/tex]
Where
[tex]n_f_i_n_a_l[/tex] and [tex]n_i_n_i_t_i_a_l[/tex] are the principal quantum numbers of the final and initial states, respectively, and -13.6 eV is the ionization energy of hydrogen.
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What must be known to determine the nature of the salt formed from a weak acid and weak base?
a. the strength of the salt only
b. the strength of the acid only
c. the strength of the base only
d. the strength of both acid and base
A solution is prepared by dissolving 0.5482 grams of iron(III) nitrate in enough water to make 100.0 mL of solution. A 10.00 mL aliquot (portion) of this solution is then diluted to a final volume of 250.0 mL. What is the concentration of Fe3 ions (M) in the final solution
Answer:
[tex]C_2=9.066x10^{-4}M[/tex]
Explanation:
Hello,
In this case, the first step is to compute the molarity of the first solution, for which we consider the molar mass of iron (III) nitrate that is 241.86 g/mol to compute the moles in 100.00 mL (0.1 L) of solution:
[tex]M=\frac{0.5482g*\frac{1mol}{241.86 g} }{0.1L}=0.0227 M[/tex]
Which is actually the concentration of iron (III) ions. Therefore, for 10.00 mL of such solution, the concentration until a dilution to 250.0 mL results being:
[tex]C_2=\frac{C_1V_1}{V_2} =\frac{0.0227M*10.00mL}{250.0mL} \\\\C_2=9.066x10^{-4}M[/tex]
Best regards.
Give the characteristics of a strong acid.
a.ionizes completely in aqueous solutions
b.has equilibrium far to the right
c.has a polar bond
d.has a weaker bond to hydrogen
e.all of the above
The characteristics of a strong acid is that it has a weaker bond to hydrogen. That is option D.
What is a strong acid?A strong acid is defined as the type of acid that completely dissociates in an aqueous solution during a chemical reaction.
Typical examples of strong acid include the following:
Hydrobromic Acid (HBr) Hydroiodic Acid (HI) Sulphuric Acid (H2SO4) Nitric Acid (HNO3) Perchloric Acid (HClO4).The characteristics of strong acids over weak acids is that they bond weakly with hydrogens.
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You put scruffy can run up to 2 meters/sec on his fastest days scruffy has a mass of 8 KG what is his maximum kinetic energy on his fastest days?
Answer:
E = 16 J
Explanation:
We have,
You put scruffy can run up to 2 m/s on his fastest days scruffy has a mass of 8 kg
It is required to find the maximum kinetic energy on his fastest days. If v is the velocity, then kinetic energy is given by :
[tex]E=\dfrac{1}{2}mv^2[/tex]
Plugging all the values,
[tex]E=\dfrac{1}{2}\times 8\times 2^2 \\\\E=16\ J[/tex]
So, the maximum kinetic energy on his fastest day is 16 J.
Which energy conversion occurs in an operating voltaic cell? A) electrical energy to nuclear energy B) chemical energy to electrical energy C) chemical energy to nuclear energy D) electrical energy to chemical energy
Answer:
B) chemical energy to electrical energy
Explanation:
The correct option is B.
Which process occurs in a voltaic cell?A voltaic cell is an electrochemical cell that uses a chemical reaction to produce electrical energy. The important parts of a voltaic cell: The anode is an electrode where oxidation occurs. The cathode is an electrode where reduction occurs.
What kind of energy is converted in a galvanic cell?A galvanic cell is an electrochemical cell that converts the free energy of a chemical process into electrical energy. A photogalvanic cell is one that generates species photochemically which react resulting in an electrical current through an external circuit.
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0.260 mol of octane is allowed to react with 0.760 mol of oxygen. How many moles of water are produced in this reaction? After the reaction, how much octane is left? Please, use conversion factors if possible.
Answer:
0.5472 moles of H₂O are produced
0.1992 moles of C₈H₁₈ were left
Explanation:
The reaction of octane (C₈H₁₈) with oxygen (O₂) is:
C₈H₁₈ + 25/2 O₂ → 8CO₂ + 9H₂O
Where 1 mole of octane reacts with 25/2 moles of oxygen to produce 8 moles of carbon dioxide and 9 moles of water
For a complete reaction of 0.760moles of oxygen there are needed:
0.760 mol O₂ ₓ (1 mole C₈H₁₈ / 25/2 moles O₂) = 0.0608 moles of C₈H₁₈
As you have 0.260 moles, the moles of octane that were left are:
0.260 mol - 0.0608 mol = 0.1992 moles of C₈H₁₈
Now, if 0.760 moles of O₂ react, the moles of water that are produced are:
0.760 mol O₂ ₓ (9 moles H₂O / 25/2 moles O₂) = 0.5472 moles of H₂O
Sodium (Na) reacts with chlorine gas to form the ionic compound NaCl. Which of the following statements is true? A The reaction leaves each atom more unstable. B Sodium gains electrons from the chlorine to form the sodium ion. C Sodium ions are anions in the ionic bond. D By reacting, each atom fills its outer energy level with electrons.
Answer:
D
Explanation:
When Na and Cl react, Na gives up one electron to Cl to fill both their valence electron shells. Both atoms are more stable, chlorine gains the electrons, and chloride is the anion.
Answer: D. After reacting, each ion has a stable octet. (For Gradpoint)
Explanation:
Maybelline Cousteau’s backup oxygen tank reads 650 torr while on her boat, where the temperature is 27 degrees C. When she dives down to the bottom of an unexplored methane lake on a recently-discovered moon of Neptune, the temperature will drop down to –183 degrees C. What will the pressure in her backup tank be at that temperature?
Answer: 180torr
Explanation:
Using P1VI/T1= P2V2/T2
where
p1= 650 torr
p2=??
T1= 27°C = 27°C + 273= 300K
T2= -183°C= -183°C +273=90K
V1= V2 ie volume is constant
SOLUTION
1 torr= 1mmHg
P1VI/T1= P2V2/T2, where V1=V2
= P1/TI= P2/T2
600/300=P2/90
P2= 600X90/300= 180 torr
An experimental procedure says to accurately weigh approximately 1 g of substance an analytical balance. Which of the following measurements are consistent with these instruction select all that apply a 1.0456 g B 1.0 g C 0.9811 g D1 gram 1.01 g E .99
Answer:
B 1.0 g
Explanation:
Hello,
In this case, by means of the significant figures we can see that 1 g has one significant figure only, for that reason, among the options, we should select one having the closest value to it, for that reason, the correct answer should be B 1.0 g as the measurement indicates the desired value.
Best regards.
why should we practice the local methods of separation?
Answer:
To obtain a desired component from the mixture
Explanation:
It is also important to be able to separate mixtures to be able to better understand how each component contributes to the properties, chemical and physical, of the resulting mixture.
How many atoms are in a sample of 1.83 moles of potassium (K) atoms? How many atoms are in a sample of 1.83 moles of potassium (K) atoms?
Answer:
Avogadro's number represents the number of units in one mole of any substance. This has the value of 6.022 x 10^23 units / mole. This number can be used to convert the number of atoms or molecules into number of moles.
1.83 moles K (6.022 x 10^23 atoms / mole ) = 1.10 x 10^24 atoms K
Explanation:
1.83 moles K (6.022 x 10^23 atoms / mole ) = 1.10 x 10^24 atoms
A 5.000 g of Compound X with molecular formula C3H4 are burned in a constant-pressure calorimeter containing 15.00 kg of water at 25 °C. The temperature of the water is observed to rise by 3.688 °C. (You may assume all the heat released by the reaction is absorbed by the water, and none by the calorimeter itself.) Calculate the standard heat of formation of Compound X at 25 °C. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.
Answer:
THE STANDARD HEAT OF FORMATION FOR C3H8 IS 9.59 KJ/MOL.
Explanation:
Mass = 5 g of C3H4
Mass of water = 15 kg
Initial temperature of water = 25 C = 25 + 273 K = 298 K
Final temperature of water = 3.688 C = 3.688 + 273 K = 276.688 K
We may make the assumptions that:
1. the specific heat of water = 4.2 J/Kg K
2. total mass of the reaction mixture = 15 kg of water + 5 g of C3H8
= 15.005 Kg
Temperature change = 298 - 276.688 = 21.312 K
heat change for the reaction
Heat = mass * specific heat * change in temperture
Heat = 15.005 * 4.2 * 21.312
Heat = 1343.10 J
EQUATION
C3H8 + 5O2 -> 3CO2 + 4H2O + heat
Number of mole = mass / molar mass
Molar mass of HCl = 36.5 g/mol
Number of mole = 5 g/ 36.5 g/mol
Number of mole = 0.14 moles
5 g of C3H8 produces 1343.10 J of heat
0.14 mole of C3H8 produces 1343.10 J
1 mole of C3H8 will produce 1343.10 / 0.14 J of heat
= 9593.57 J
= 9.59 kJ of heat.
The standard heat of formation for C3H8 is 9.59 kJ/mol.
A doctor orders 4.0 mg of morphine. The vial of morphine on hand is 20. mg per 2.0 mL . How many milliliters of morphine should you administer to the patient?
In 1782 a French chemist named ________ proposed a systematic nomenclature for naming chemical compounds.
Answer:
Louis-Bernard Guyton De Morveau
Explanation:
He is who proposed the first systematic nomenclature for naming chemical compounds.
How is the salt formed in a neutralization reaction written in a chemical reaction?
Answer:
A neutralization reaction between an acid and a base will produce a salt and water. In a neutralization reaction, the acid will produce H+ ions that react to neutralize the OH- ions produced by the base, forming neutral water. ... A weak acid + a strong base in an acid/base neutralization reaction will form a basic salt
Explanation:
An analytical chemist is titrating 60.5mL of a 0.8700M solution of benzoic acid HC6H5CO2 with a 0.3600M solution of KOH . The pKa of benzoic acid is 4.20 . Calculate the pH of the acid solution after the chemist has added 172.mL of the KOH solution to it. Note for advanced students: you may assume the final volume equals the initial volume of the solution plus the volume of KOH solution added. Round your answer to 2 decimal places.
Answer:
The correct answer is 12.6.
Explanation:
The formation of benzoate takes place when potassium hydroxide reacts with benzoic acid, due to the presence of a weak acid and its conjugated base the solution will act as a buffer. In the given question, the molarity of benzoic acid given is 0.8700 M and its volume is 60.5 ml. Therefore, the moles of benzoic acid will be,
Moles = molarity * volume of solution
= 0.8700 M * 60.5 ml = 52.365 m mol or 0.052365 moles
On the other hand, the molarity of KOH given is 0.3600 M and the volume given is 172 ml. Therefore, the moles of KOH added will be,
Moles = 0.3600 * 172 = 61.92 m moles or 0.06192 moles
Out of this 61.92 m mol, only 52.365 m mol of KOH will react with the benzoic acid. The moles of KOH, which remain unreactive is,
61.92 m moles - 52.365 m moles = 9.285 m moles or 0.009285 moles
The formula for calculating molarity is number of moles / volume of solution in liters
The total volume of the solution is 172 ml + 60.5 ml = 232.5 ml or 0.2325 L
The molarity of KOH will be,
Molarity = 0.009285 moles / 0.2325 L = 0.0395 M
The dissociation of KOH takes place completely to produce hydroxide ion.
pOH = -log[0.0395] = 1.4
pH + pOH = 14
pH = 14 - 1.4 = 12.6
1.What volume of 0.871 M oxalic acid contains 86.9 g of oxalic acid (H2C2O4)?
Answer:
1.11 L
Explanation:
Given data
Molarity of the oxalic acid solution (M): 0.871 MMass of oxalic acid (m): 86.9 gStep 1: Calculate the moles corresponding to 86.9 g of oxalic acid
The molar mass of oxalic acid is 90.03 g/mol.
[tex]86.9g \times \frac{1mol}{90.03g} = 0.965 mol[/tex]
Step 2: Calculate the volume of a 0.871 M solution that contains 0.965 moles of oxalic acid
The molarity is equal to the moles of solute (n) divided by the volume of the solution (V).
[tex]M = \frac{n}{V} \\V = \frac{n}{M} = \frac{0.965mol}{0.871 mol/L} =1.11 L[/tex]
Calculate the theoretical yield in moles of magnesium chloride when 37 grams of Mg(s) react with 38 grams of HCl(aq).Write the answer using 2 decimal places and do not use scientific notation.
Answer:
The correct answer is 0.52 moles.
Explanation:
Based on the given question, 37 grams of magnesium reacts with 38 grams of HCl to produce MgCl2 or magnesium chloride. The reaction is:
Mg (s) + 2HCl (aq) ⇒ MgCl2 (aq) + H2 (g)
There is a need to find the theoretical yield in moles of MgCl2. The formula for calculating the no. or moles is mass/molar mass. Therefore, moles of magnesium is 37/24 = 1.54 and moles of HCl will be 38/36.5 = 1.04.
From the reaction it is clear that one mole of magnesium reacts with two moles of HCl, as lesser quantity of HCl is present in the given case, therefore, HCl will be the limiting reagent.
Now theoretical moles of magnesium chloride will be,
= moles of HCl / 2
= 1.04 / 2
= 0.52 moles
A 10.17-g sample of solid sodium bicarbonate (the active ingredient in baking soda) completely decomposes into solid sodium hydroxide and carbon dioxide gas when heated. After the sodium hydroxide cools, it has a mass of 4.84 g. According to the law of conservation of mass, what mass of carbon dioxide must have been formed?
Answer:
5.33 g
Explanation:
Let's consider the balanced reaction for the complete decomposition of solid sodium bicarbonate to form solid sodium hydroxide and carbon dioxide gas when heated.
NaHCO₃(s) → NaOH(s) + CO₂(g)
According to Lavoisier's law of conservation of mass, the sum of the masses of the reactants is equal to the sum of the masses of the products. Then,
m(NaHCO₃) = m(NaOH) + m(CO₂)
m(CO₂) = m(NaHCO₃) - m(NaOH)
m(CO₂) = 10.17 g - 4.84 g
m(CO₂) = 5.33 g
