Answer:
787.4g
Explanation:
The dimensions of the iron block is given as follows;
L = 10cm, B = 5cm, H = 2cm
Volume = L × B × H
Volume = 10 × 5 × 2
Volume = 100cm³
Density of iron metal = 7.874 g/cm³
Using the formula;
Density = mass/volume
Mass = density × volume
Mass = 7.874 × 100
Mass of iron = 787.4g
The atomic mass of calcium is calculated by adding the mass (amount) of
A) Protons and Electrons
B) Protons and Neutons
C) Electrons and Neutons
D) Protons and Protons
Answer:
B. Protons and Neutrons
Answer:
Option"B" is correct.
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An inorganic salt is composed of 17.6% sodium, 39.7% chromium, and 42.8% oxygen. What is the empirical formula of this salt?
Salt is often used to melt ice on roads during the winter because it lowers the freezing/melting point of water. When salt dissolves in water, individual Na and Cl- ions break away from the salt lattice and become surrounded by water molecules. Why would this cause ice to melt
Answer:
See explanation
Explanation:
The addition of an impurity lowers the melting point of a solid. If we add salt to ice, the melting point of the ice is lowered.
As this salty water is in contact with the ice, more of the salt dissolves to yield Na^+ and Cl^- and leads to the melting of more ice.
Freezing point is a colligative property hence it is affected by the presence of impurities. Hence, the addition of NaCl causes ice to melt faster.
The three aspects of the measuring process are units, systems, and instruments.
O True
O False
NEXT QUESTION
ASK FOR HELP
TURNI
Answer:
the answer for that is false
Answer:
false
Explanation:
the ans is falsehope it helpsHow many moles of Cd and of N are contained in 132.4 g of Cd(N03)2-4H20? (b) How many molecules of water of hydration are in this same amount?
Answer: The given amount of [tex]Cd(NO_3)_2.4H_2O[/tex] contains 0.430 moles of Cd, 0.860 moles of N and [tex]2.59\times 10^{23}[/tex] molecules of water.
Explanation:
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
Given mass of [tex]Cd(NO_3)_2.4H_2O[/tex] = 132.4 g
Molar mass of [tex]Cd(NO_3)_2.4H_2O[/tex] = 308.5 g/mol
Plugging values in equation 1:
[tex]\text{Moles of }Cd(NO_3)_2.4H_2O=\frac{132.4g}{308.5g/mol}=0.430 mol[/tex]
1 mole of [tex]Cd(NO_3)_2.4H_2O[/tex] contains 1 mole of Cd, 2 moles of nitrogen atom (N), 10 moles of oxygen atom (O) and 8 moles of hydrogen atom (H).
So, 0.430 moles of [tex]Cd(NO_3)_2.4H_2O[/tex] will contain = [tex](1\times 0.430) = 0.430mol[/tex] of Cd and [tex](2\times 0.430)=0.86mol[/tex] of N
According to the mole concept:
1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of molecules
So, 0.430 moles of [tex]Cd(NO_3)_2.4H_2O[/tex] will contain = [tex]\frac{6.022\times 10^{23}}{1mol}\times 0.430mol=2.59\times 10^{23}[/tex] number of water molecules.
Hence, the given amount of [tex]Cd(NO_3)_2.4H_2O[/tex] contains 0.430 moles of Cd, 0.860 moles of N and [tex]2.59\times 10^{23}[/tex] molecules of water.
Wich one is it - this is biochemistry
Answer:
O=O is not a compound; it's a molecule.
Answer:
it is O double bond
Explanation:
because it is not attached with another different molecule like Hydrogen Carbon Sulfur etc. H2O or CO2(these are compounds)
ASAP
Which of the following describes a characteristic of water that makes it cohesive in nature?
A - It has a partial negative charge on hydrogen and a partial positive charge on oxygen.
B - It has a linear molecular structure with H-O-H arranged in a straight line.
C - It has a vast electronegativity difference between its constituent atoms.
D - It requires a high amount of heat to raise or drop its temperature.
The answer is C.
The vast difference in electronegativity of the oxygen and hydrogen in water, the O-H bond is polar.
The characteristic of water that makes it cohesive in nature is that It has a vast electronegativity difference between its atoms. So, option C is correct one.
Why water is cohesive in nature?The water molecule contains two hydrogen atoms and oxygen atom.
The electronegativity of hydrogen atoms and oxyegen atom is 2.1 and 3.44
Due to high electronegativity of oxygen ,it can attract the bonded pair of electron of hydrogen and form a strong bond and make it cohesive in nature.
What are major characteristics of water?The water molecule have unique characteristics among all some are given below.
Water is polar, with partial positive charge on two hydrogen and partial negative charge on one oxygen.
Water is act as solvent and dissolves the polar and ionic substance.Water has high heat of vaporization.Water has cohesive and adhesive properties.Water has high heat capacity.learn about water molecule Here,
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The presence of which gas makes the planets Uranus and Neptune appear blue?
a. helium
b. hydrogen
c. methane
d. nitrogen
Answer:
C. METHANE
Explanation:
The blue color of both the ice giants can be contributed to the presence of methane in their upper atmospheres. Methane absorbs most of the red light incident on the planets which makes them appear blue in color.
from the equation 2PbO + C = 2Pb + CO2, detemine which one is reactant is oxidised and which is reduced.
Answer:
Explanation:
C is oxidised because C up to C+4
PbO is reduced because PbO from Pb2+ down to Pb0
Answer:
lead (Pb) is reduced carbon is oxidized
In a synthesis experiment you obtain a sample of product on which you do a melting point determination and find a melting point range of 114 to 125 degrees Celsius. The sample is supposed to be acetylsalicyclic acid. What preliminary conclusion(s) can you reach from this one determination
Answer:
The melting point determination may need improvement- it may not have been done properly, and make sure it was repeated at least once.
Explanation:
Given that we know the actual melting point of pure acetylsalicyclic acid to be 135°, it follows that the process followed to obtain the melting point range of 114 to 125 degrees Celsius must be inaccurate.
Therefore, we can conclude that, the melting point determination may need improvement. It may not have been done properly, and we must make sure it is repeated at least once.
Why does increasing the temperature make a solid dissolve faster?
- The solvent molecules bump into the solid more often.
- The solid is melted before mixing into the liquid.
- The chemical bonds of the solid are broken faster.
- The pressure of the solute on the solid is increased.
Answer:
The solvent molecules bump into the solid more often
Explanation:
Increasing the temperature makes a solid dissolve faster because the solvent molecules bump into the solid more often.
What happens when you increase the temperature of the solvent?If we heat the solvent, the average kinetic energies of its molecules increase. Hence, the solvent is able to dislodge more particles from the surface of the solute. Thus, increasing the temperature increases the solubilities of substances. For example, sugar and salt are more soluble in water at higher temperatures.
Does raising the temperature make a substance dissolve faster in a solvent?The temperature of the solvent is another factor that affects how fast a solute dissolves. Generally, a solute dissolves faster in a warmer solvent than it does in a cooler solvent because particles have more energy of movement.
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ayo could u help me out
10. As electrons move through the electron-transport chain,
they lose energy, which is used to form
A. NAD.
B. ADP
C. ATP.
D. GBP
Answer:
NAD
Explanation:
mark me brainlist please
Answer:
They lose energy which is used to form ATP
Chemistry!! Help me! And explain step by step!
1st part is ure answer --> 2M
Given mass -> 58 grams
mass of NaCl -> 58.44 approx -> 58 any
moles given-> 1 moles
[tex]Molarity = \frac{moles}{vol \: in \: lts} [/tex]
[tex]Molarity = \frac{1}{0.5} = \frac{10}{5} \\Molarity = 2M[/tex]
Give reasons. a. Troposphere is affected maximum by human activities.
Answer:
it is where the ozone layer is locate which is affected by human activities
A gas occupies 210 mL at -73°C to have the same gas occupy 360 mL:
should the temperature be increased or decreased?
what is the new temperature? __ K
Answer:
a. The temperature should be increased.
b. 342.86K
Explanation:
Using Charles law equation as follows:
V1/T1 = V2/T2
Where;
V1 = initial volume (mL)
V2 = final volume (mL)
T1 = initial temperature (K)
T2 = final temperature (K)
According to this question, the following information were given:
V1 = 210mL
V2 = 360mL
T1 = -73°C (-73 + 273 = 200K)
T2 = ?
Using V1/T1 = V2/T2
210/200 = 360/T2
Cross multiply
200 × 360 = 210 × T2
72000 = 210T2
T2 = 72000/210
T2 (new temperature) = 342.86K
Which statement describes a condensation reaction?
A. monomers break away when one forms a double bond monomers break away with the addition of a water molecule.
B. Two monomers combine when one adds to the double bond of another.
C. Two monomers form a new bond with the loss of a water molecule .
The statement that describes a CONDENSATION reaction is that two monomers form a new bond with the loss of a water molecule . That is option C.
CONDENSATION REACTION involves the combination of two or more molecules(monomers) of water. In reaction, a new bond is usually formed.
The characteristics of a condensation reaction includes:
formation of complex molecules (combination of two smaller monomers),water is usually given off as by product it requires a catalyst for a complete reaction to occurA reaction is called a condensation reaction because a small molecule such as water is released as a byproduct.
A typical example of a condensation reaction is the condensation of amino acids to form dipeptide. The −OH from the carboxyl group of one amino acid combines with a hydrogen atom from the amine group of the other amino acid to produce water.
Therefore, the statement that describes a CONDENSATION reaction is that two monomers form a new bond with the loss of a water molecule. That is option C
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For his science fair project, Martin studied the growth of trumpet vines. He grew 20 trumpet vines. All of the conditions were the same, except that he grew 10 in a flower bed without support and 10 in a flower bed near a trellis. The stems of the vines near the trellis twisted around the trellis, and these Yines grew tall and seemed much healthier than the vines grown without a trellis. In fact, four of the vines grown without a trellis died. Which characteristic of living things were the trumpet vines displaying as the stems twisted around the trellis?
A. Movement
B. Response to a stimulus
C. Use of energy
D. Reproduction
Answer:
it's B
Explanation:
Climbing plants require an external support to grow vertically and enhance light acquisition. Vines that find a suitable support have greater performance and fitness than those that remain prostrate. Therefore, the location of a suitable support is a key process in the life history of climbing plants
Which of the following would not be considered matter?
clouds
trees
rain
air
light
Answer:
light
Explanation:
Have a nice day
Answer:
light
Explanation:
that B) My color is sickle: I have a drop of water in my body when I was given heat, white powder was formed So who am i Lets identify. Write my chemical molecular formula
Explanation:
i don't understood your question ⁉️
and what do u mean by my color is sickle
Temperature (°C) 5
Heating Curve for Water
160
140
2 120
100
80
60
40
20
0
-20
1 2 3 4 5 6 7
Time (min)
8
9
10
At what temperature does the solid start melting?
0 -20°C
0°C
20°C
80°C
Answer:
Showing results for Temperature (°C) 5 Heating Curve for Water 160 140 2 120 100 80 60 40 20 0 "-20" 1 2 3 4 5 6 7 Time (min) 8 9 10 At what temperature does the solid start melting?
HELP PLEASE 15 POINTS
The rate law for a reaction is found to be rate = k[X]4. By what factor does the rate increase if [X] is doubled?
How many moles of oxygen are required to react completely with 5 mol C8H18?
Answer:
62.5 moles of O₂.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2C₈H₁₈ + 25O₂ —> 16CO₂ + 18H₂O
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Finally, we shall determine the number of mole of O₂ needed to react with 5 moles of C₈H₁₈. This can be obtained as shown below:
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Therefore, 5 moles of C₈H₁₈ will react with = (5 × 25) / 2 = 62.5 moles of O₂.
Thus, 62.5 moles of O₂ is needed for the reaction.
why is the Dna molecule able to open up and close?
Answer:
The breaking of the hydrogen bonds due to the force relieves the torsional stress stored in a double helix. As a result, the nucleotide strands rotate more freely about the axis of a helix and start unwinding. ... The DNA unzipping and the DNA unwinding result in a structural transformation from dsDNA to ssDNA.
19. If 23.4 grams of hydrogen gas were produced by the reaction below, how many grams of aluminum chloride were produced? (2 points) 2 Al + 6 HCl yields 2 AlCl3 + 3 H2 516 g AlCl3 774 g AlCl3 1030 g AlCl3 1550 g AlCl3
Answer:
1040
Explanation:
you can use the mole to mole ratios of aluminum chloride and hydrogen gas,you first have to find the number of moles of hydrogen gas..the number of moles of hydrogen gas are 11.7(23.4/2)
2AlCl3+3H2
2 : 3
x :11.7
3x/3=23.4/3
x=7.8g/mol
then find the number of grams of aluminum chloride
m=n×mr
=7.8×133.341
=1040g
I hope this helps and sorry if it's wrong
What is the oxidation state of S in HSO4^2-? (A.P.E.X)
I think there is a typo because I've never seen HSO4 2- before in my life. It should be HSO4-. For that, H is 1+ and each Oxygen is 2-0 totaling 8-. So the oxidation state of sulfur +1 - 8 = 7
So the oxidation state of sulfur is +6
calculate the maximum mass of ethanol that could be obtained from 30.0g of glucose
Answer:
15.3g
Explanation:
C6H12O6 → 2C2H5OH + 2CO2
1 mol C6H12O6 = 180g
1 mol CH3-CH2-OH = 46g
From 180g glucose ethanol can get = 92g
30g glucose ethanol gives us = (92*30)/180 = 15.33g
How much heat is added if .0948g of water is increased in temperature by .728 degrees C?
.289 J
.803 J
1.46 J
.055 J
Answer:
0.289J of heat are added
Explanation:
We can relate the change in heat of a substance with its increasing in temperature using the equation:
q = m*ΔT*S
Where Q is change in heat
m is mass of substance (In this case, 0.0948g of water)
ΔT = 0.728°C
S is specific heat (For water, 4.184J/g°C)
Replacing:
q = 0.0948g*0.728°C*4.184J/g°C
q = 0.289J of heat are added
A(n) _____ is a hydrocarbon in which one or more hydrogen atoms is replaced by a -COOH and a -NH2 group. aldehyde carboxylic acid alcohol amino acid
Answer:
Amino Acid
Explanation:
It's part of the Amino group, which are substituted hydrocarbons.
When NH₂ and COOH replaces hydrogens on the same carbon atom in a molecule, an Amino acid is formed.
What group is a COOH?
COOH : a Carboxylic Acid group!
How many grams of solute is there in 250 mL of a 0.10M CaCl2 solution ?
Answer:
2.775 g
Explanation:
Given that;
Number of moles = concentration × volume
Concentration = 0.10M
Volume =250 mL
Number of moles = 250/1000 × 0.10
Number of moles = 0.025 moles
Also;
Number of moles = mass/molar mass
Molar mass of CaCl2= 111 g/mol
Mass = Number of moles × molar mass
Mass = 0.025 moles × 111 g/mol
Mass= 2.775 g
