By definition of atomic number, the correct answers are:
"The number of protons is given by the atomic number, which increases by one moving from left to right across each row of the periodic table." and "The number of protons is given by the atomic number, which increases by one moving down in its column in the periodic table."You have to know that atoms are made up of a nucleus made up of protons and neutrons, and a shell made up of electrons. Protons are positively charged, while neutrons are electrically neutral (that is, they have zero charge). Therefore the atomic nucleus always has a positive charge. On the other hand, electrons are negatively charged.
The atomic number is the total number of protons that make up the atomic nucleus of a given chemical element and is represented by the letter Z.
An atom is naturally neutral and has the same number of electrons and protons.
The atomic number is used to classify the elements within the periodic table of elements, going from the smallest to the largest number of protons in the nucleus as you progress through the rows and columns of the table. That is, as you travel a period (row) from left to right and as you travel a group (column) from top to bottom, the atomic number increases.
In summary, the correct answers are:
"The number of protons is given by the atomic number, which increases by one moving from left to right across each row of the periodic table." and "The number of protons is given by the atomic number, which increases by one moving down in its column in the periodic table."Learn more about the atomic number: https://brainly.com/question/1262368?referrer=searchResults
Answer:
The answer is "The number of protons is given by the atomic number, which increases by one moving from left to right across each row of the periodic table."
Explanation:
If you look at the periodic table, the elements atomic numbers increase from left to right by one. Therefore, the protons also increase by one from left to right because the number of protons in an element is the same as the atomic number.
1. Consider the following thermochemical reaction for kerosene:
2 C12H26(l) + 37 O2(g) 24 CO2(g) + 26 H2O(l) + 15,026 kJ
(a) When 21.3 g of CO2 are made, how much heat is released?
(b) If 500.00 kJ of heat are released by the reaction, how grams of C12H26 must have been consumed ?
(c) If this reaction were being used to generate heat, how many grams of C12H26 would have to be reacted to generate
enough heat to raise the temperature of 750g of liquid water from 10oC to 90oC?
2. Consider the reaction: NaNO3(s) + H2SO4(l) → NaHSO4(s) + HNO3(g) ΔH° = 21.2 kJ
How much heat must absorbed by the reaction system to convert 100g of NaNO3 into NaHSO4(s)?
3. What is the enthalpy change when 49.4 mL of 0.430 M sulfuric acid reacts with 23.3 mL of 0.309 M potassium
hydroxide?
3.
H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(l) ΔH° = –111.6 kJ/mol
do you have the specific heat for part 2?
Which of the following is an example of a scientific theory?
Matter can be neither created nor destroyed.
Force equals mass times acceleration.
Matter behaves the way it does because it is made of atoms.
There is probably life on Mars.
C. Matter behaves the way it does because it is made of atoms.
Answer:
Matter can neither be created nor destroyed
Explanation:
Mark me. as brainliest
In water, a substance that ionizes completely in solution is called a
Answer:
please mark me brainliest
Explanation:
In water, a substance that ionizes completely in solution is called a weak electrolyte.
Answer: strong electrolyte.
Explanation: In water, a substance that ionizes completely in solution is called a. a. weak electrolyte.
HELP! Which type of model best represents simple molecules?
A. wire
B. ribbon
C. structural formula
D. Lewis dot
Which of the following has the greatest effect on colligative properties?
A. Calcium chloride (CaCl2)
B. Sodium chloride (NaCl)
C. Aluminum Nitrate (Al(NO3)3)
D. Epsom salt (MgSO4)
Answer:
C. Aluminum Nitrate (Al(NO3)3)
Explanation:
This is because, when Aluminium nitrate dissolves in water, it dissociates to form four ions ( one aluminium ion and three nitrate ions ). Since colligative property depends on number of particles or ions present ( roult's law ), this will create much effect.
[tex]Al(NO _{3} )_{3(aq)} → Al {}^{3 + } _{(aq)} + 3NO {}^{ - } _{(aq)}[/tex]
Answer:
aluminum nitrate (Al(NO3)3)
it has the greatest effect on collimation properties .
Explanation:
(c) is correct option
What is the mass grams that are in 3.52 × 10²⁵ molecules of I₂
Answer:
As you know, one mole of any substance contains exactly
6.022
⋅
10
23
molecules of that substance - this is known as Avogadro's number.
Notice that you're dealing with more than
6.022
⋅
10
23
molecules of carbon dioxide, which means that you'll also be dealing with more than one mole of the compound.
More specifically, you'll have
1.5
⋅
10
26
molecules
⋅
1 mole CO
2
6.022
⋅
10
23
molecules
=
2.491
⋅
10
2
moles CO
2
Now, a substance's molar mass tells what the mass of one mole of that substance is. In carbon dioxide's case, its molar mass is equal to
44.01 g/mol
, which means that every mole of
CO
2
will have a mass of
44.01 g
.
In your case,
2.491
⋅
10
2
moles of
CO
2
would have a mass of
2.491
⋅
10
2
moles CO
2
⋅
44.01 g
1
mole CO
2
=
109.63 g
Rounded to two sig figs, the number of sig figs you have for the number of molecules of
CO
2
, the answer will be
m
C
O
2
=
110 g
What best describes the goals of scientific investigation and technological development?
Both scientific investigation and technological design aim to solve problems by making more cost-effective and affordable products.
Both scientific investigation and technological design aim to conduct experiments to uncover new information and share the results.
Scientific investigation aims to design products that can make use of new information, whereas technological development aims to conduct experiments to improve affordability and availability.
Scientific investigation aims to design and implement an experiment to learn new information, whereas technological development aims to design a product to solve a problem.
Answer: D. Scientific investigation aims to design and implement an experiment to learn new information, whereas technological development aims to design a product to solve a problem.
Explanation:
Convert the concentration of 0.700 M Na2SO4 to g/mol
To convert from mass concentration to molar concentration we use the formula;
Mass concentration = molar concentration * molar mass
Molar concentration of Na2SO4 = 0.700 M
Molar mass of Na2SO4 = 2(23) + 32 + 4(16) = 142 gmol-1
Hence;
Mass concentration = 0.700 M * 142 gmol-1
Mass concentration = 99.4 g/mol
To know more about concentration, see
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Why must beta particles be used to detect leaks in a pipe?
Why must beta particles be used to detect leaks in a pipe?
A. Beta particles will not be absorbed by the soil like gamma radiation, but won't pass through the pipe before reaching the leak like alpha radiation would.
B. Beta particles will not cause an electrical discharge like alpha particles when they interact with the metal pipe, or contaminate the water like gamma radiation.
C. Beta particles are not used, only alpha particles are used because they are not harmful to humans.
D. Beta particles will not be absorbed by the soil like alpha particles, but won't pass through the pipe before reaching the leak like gamma radiation would.
Should be D, because alpha particles are absorbed by soil and gamma isn't
Beta particles will not be absorbed by the soil like alpha particles, but won't pass through the pipe before reaching the leak.
What is Beta particle?This type of particle is a high-speed electron and is derived from the process of beta decay.
It is used to detect leaks in pipe because it will not be absorbed by the soil like alpha particles, but won't pass through the pipe before reaching the leak like gamma radiation would.
Read more about Beta particle here https://brainly.com/question/14324290
Sodium ethoxides are made by direct reaction of:
a. Sodium hydroxide and dry ethanol
b. Sodium metal and 70% ethanol
c. Sodium hydroxide and 70% ethanol
d. Sodium metal and dry ethanol
Answer:c
Explanation:
Heating water makes most solids in it
soluble, and it makes gases
soluble.
Increasing the pressure on a gas above water makes the gas
soluble. Compounds with comparatively stronger ionic bonds are
soluble.
Answer:
1. more
2. less
3. more
4. less
Explanation:
Assuming that no equilibria other than dissolution are involved, calculate the concentration of all solute species in each of the following solution of salt in contact with a solution containing a common ion. Show that changes in the initial concentrations:
PbCl2(s) in 0.631 M MgCl2 (MgCl2 is strong electrolyte)
Ksp PbCl2 = 1.6 × 10−5
The concentration of all solute species in the solution are:
[tex][Mg^{2+} ] = 0.631 M \\ [Pb] = 1.0 \times 10^{-5} M \\[Cl^{-} ] = 1.26 M[/tex]
MgCl₂ (0.631 M) is a strong electrolyte that dissociates according to the following equation.
MgCl₂(aq) ⇒ Mg²⁺(aq) + 2 Cl⁻(aq)
Considering the molar ratios, the initial concentrations of Mg²⁺ and Cl⁻ are:
[tex]\frac{0.631 mol MgCl_2}{L} \times \frac{1molMg^{2+} }{1molMgCl_2} = \frac{0.631molMg^{2+}}{L} \\\frac{0.631 mol MgCl_2}{L} \times \frac{2molCl^{-} }{1molMgCl_2} = \frac{1.26molCl^{-}}{L}[/tex]
Cl⁻ is a common ion between MgCl₂ and PbCl₂. To consider the solution equilibrium for PbCl₂ (a sparingly soluble salt), we will make an ICE chart.
PbCl₂(s) ⇄ Pb²⁺(aq) + 2 Cl⁻(aq)
I 0 1.26
C +x +2x
E x 1.26+x
The solubility product constant, Ksp, is:
[tex]Ksp = 1.6 \times 10^{-5} = [Pb^{2+} ][Cl^{-} ]^{2} = (x) (1.26+x)^{2}[/tex]
Since 1.26 >>> x, 1.26 + x ≈ 1.26.
[tex]Ksp = 1.6 \times 10^{-5} = (x) (1.26)^{2}\\x = 1.0 \times 10^{-5}[/tex]
The concentration of all solute species in the solution are:
[tex][Mg^{2+} ] = 0.631 M\\ [Pb] = x = 1.0 \times 10^{-5} M\\[Cl^{-} ] = 1.26+x = 1.26 M[/tex]
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At a constant temperature, a sample of gas occupies 1.5 L at a pressure of 2.8 ATM. What will be the pressure of this sample, in atmospheres, if the new volume is 0.92 L?
Using boyles law
[tex]\boxed{\sf v\propto \dfrac{1}{p}}[/tex]
[tex]\\ \sf\longmapsto P_1V_1=P_2V_2[/tex]
[tex]\\ \sf\longmapsto P_2=\dfrac{P_1V_1}{V_2}[/tex]
[tex]\\ \sf\longmapsto P_2=\dfrac{2.8\times 1.5}{0.92}[/tex]
[tex]\\ \sf\longmapsto P_2=\dfrac{4.2}{0.92}[/tex]
[tex]\\ \sf\longmapsto P_2=4.56atm[/tex]
[tex]\\ \sf\longmapsto P_2\approx 4.6atm[/tex]
Answer:
[tex]\boxed {\boxed {\sf 4.6 \ atm}}[/tex]
Explanation:
We are asked to find the new pressure given a change in volume. We will use Boyle's Law, which states the volume of a gas is inversely proportional to the pressure. The formula for this law is:
[tex]P_1V_1= P_2V_2[/tex]
Initially, the gas occupies 1.5 liters at a pressure of 2.8 atmospheres.
[tex]1.5 \ L * 2.8 \ atm = P_2V_2[/tex]
The volume is changed to 0.92 liters, but the pressure is unknown.
[tex]1.5 \ L * 2.8 \ atm = P_2* 0.92 \ L[/tex]
We are solving for the final pressure, so we must isolate the variable P₂. It is being multiplied by 0.92 liters. The inverse operation of multiplication is division, so we divide both sides by 0.92 L.
[tex]\frac {1.5 \ L * 2.8 \ atm}{0.92 \ L} = \frac{P_2* 0.92 \ L}{0.92 \ L}[/tex]
[tex]\frac {1.5 \ L * 2.8 \ atm}{0.92 \ L}= P_2[/tex]
The units of liters cancel each other out.
[tex]\frac {1.5 * 2.8 \ atm}{0.92 }=P_2[/tex]
[tex]\frac {4.2}{0.92} \ atm= P_2[/tex]
[tex]4.565217391 \ atm = P_2[/tex]
The original measurements of pressure and volume have 2 significant figures, so our answer must have the same. For the number we calculated, that is the tenths place. The 6 in the hundredth place tells us to round the 5 up to a 6.
[tex]4.6 \ atm \approx P_2[/tex]
The pressure is approximately 4.6 atmospheres.
cuales son las caracteristicas de el livermorio
Answer:
Livermorium is a radioactive, artificially produced element about which little is known. It is expected to be a solid and classified as a metal. It is a member of the chalcogen group. Livermorium has four isotopes with known half-lives, all of which decay through alpha decay
Help please due tomorrow
Answer:
3rd option - humans chose the potential parents for crosses based on desired characteristics.
Explanation:
Artificial selection is the identification by humans of desirable traits in plants and animals, and the steps taken to enhance and perpetuate those traits in future generations.
Given the reactants of the chemical reaction that will take place in Part D (construction of a lead concentration cell) prior to the assembly of the cell, determine the type of chemical reaction it is. Hint: Determine the products of the reaction.
Answer:
hi
Explanation:
Which of the following metals will liberate hydrogen from dilute HCL? A. Ag B.Au C.Hg D.Sn
Answer:
ag and au are sure not to react. but hg and sn might or might not
which are the nutrients essential to us
Explanation:
carbohydrate,fat,protein, vitamin, mineral, water
Answer:
There are six major nutrients: Carbohydrates (CHO), Lipids (fats), Proteins, Vitamins, Minerals, Water.
Draw Lewis structures to show how H+ is transferred when HNO₂ and NH₃ react with each other. The Lewis structure of HNO₂ is:
Attached are the Lewis structures:
Hope it helps...
[tex] \: \: \: [/tex]
What is the quantity of heat evolved when 15g of CH4 is completely burned in air? Given that CH4+2O2→ CO2+2H2OΔH=-890Kj/mol
Answer:
You're going to have to convert the grams to moles, and then multiply that with the ratio of heat produced to the ratio of CH4
Are acids harmful to work with.
Answer:
yes it is
Explanation:
because there are some acid which really harm skin.
Which of the following statements accurately describes how a catalyst acts in a chemical reaction?
I. Decreases the kinetic energy of the reaction
II. Is not consumed by the reaction
III. Increases the equilibrium constant
IV. Reduces the required activation energy
a) II, III, and IV only
b) I and III only
c) I and II only
d) II and IV only
Answer:
d) II and IV only.
Explanation:
A catalyst increases the kinetic energy of reactant molecules which increases the magnitude of collision. These then decreases the activation energy . A catalyst is not consumed by reaction because it is neither reactant nor a product, hence has no effect on equilibrium constant.
[tex].[/tex]
Answer:
A
Explanation:
it speed up a chemical reaction without being consumed by the reaction and increases the reaction rate by lowering the activation energy for a reaction but the average kinetic energy of the molecules remains the same well the required energy decreases
A number is three times the difference between twenty and the number. What is the number?
Answer:
the number is 7
Explanation:
"Three times" means multiply by 3
"Difference" means subtract
"Sum" means add
3(x - 7) = 23 - (3x + 2)
3x - 21 = 23 - 3x - 2
3x - 21 = 21 - 3x
6x = 42
x = 7
why styrene undergoes and ionic polymerization at a faster rate than p methoxystyrene
Answer:
In styrene, there is a phenyl group which is electron-withdrawing. So the electronic density in the double bonds increases, hence easy to associate as monomers. While in methoxystyrene, there is a carbonyl group which is not electron deficient. so no easy association with monomers.
Explanation:
[tex]{ \sf{styrene \: is \: phenylethene \: }} \\ { \sf{its \: polymer \: is \: polystyrene}}[/tex]
In the reaction A + B + C + D, what are the reactants?
O A. Just B
B. Cand D
O c. A and B
O D. A and C
Answer:
C.
Explanation:
I believe that it should be A and B.
The surface of silver metal, Ag(s), became tarnished when it was exposed to oxygen, producing Ag2O. In Ag2O, the oxidation state of silver is 1. According to this information, silver metal was _____. Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices reduced
Answer: The silver metal was OXIDIZED.
Explanation:
OXIDATION is defined as loss of electrons and increase in oxidation number of an atom.
Oxidation number is the charge on an ion in an ionic compound or the charge that an atom in a covalent compound would have it it were ionic. There are basic rules governing oxidation number, they include:
--> the oxidation number of elements in their free states is ZERO. Example O2, Cl2,Na, Al, Ag.
-->The oxidation number for an ion is the same as the size and sign of the charge on the ion. For example the oxidation number of Zn2+ is +2.
--> the sum of all the oxidation numbers of the elements in a compound is zero.
--> oxidation numbers are always written with either a positive or a negative sign.
On the other hand, reduction is the opposite of oxidation. As oxidation is taking place, reduction is also taking place. Reduction involves:
--> Gain of electron and
--> decrease in oxidation number
From the question, the silver metal had ZERO as it's oxidation number because it's in free state. After being exposed to oxygen to form silver oxide, the oxidation number became +1.
Since there is an increase in the oxidation number, the silver metal was OXIDIZED
Compared to an atom of C-12, an atom of C-14 has
A) fewer protons
C) more neutrons
B) fewer neutrons
D) more protons
Explanation:
Carbon-12 atoms have stable nuclei because of the 1:1 ratio of protons and neutrons.
Carbon-14 atoms have nuclei which are unstable. C-14 atoms will undergo alpha decay and produce atoms of N-14. Carbon-14 dating can be used to determine the age of artifacts which are not more than 50,000 years old.
ort
Which is a primary alcohol?
0 3-pentanol
2-propanol
1-ethanol
4-octanol
urvey
Lig A Moving to another question will save this response.
Answer:
1 ethanol is right answer
Explanation:
CH3- CH2-OH
Which substance will sublimate when in the solid phase at room temperature and pressure?
Select the correct answer below:
A) carbon dioxide
B) water
C) mercury
D) helium
Answer:
I think carbon dioxide is right answer
Name the following alkane molecule:
A. methylpentane
B. 2-methylpentane
C. 2-ethylpentane
Answer:
B
Explanation:
its upside down but I'm 99% sure
