All categories

3 years ago

When there are 165.0grams of reactants, what is the mass of the products for that reaction?

Chemistry

1 answer:

vfiekz [6]3 years ago

3 0

Answer:

165.0 grams

Explanation:

The law of conservation of mass tells us that the mass of the reactants will be equal to the mass of the products. Therefore, if we begin with 165.0 grams of mass, that is how much there will be at the end in the products, even if it's in different forms.

You might be interested in

HELP PLEASE I HAVE A TEST TODAY AND I DON'T UNDERSTAND ANY OF THIS...

myrzilka [38]

Answer:

About 67 grams or 67.39 grams

Explanation:

First you would have to remember a few things:

enthalpy to melt ice is called enthalpy of fusion. this value is 6.02kJ/mol

of ice

it takes 4.18 joules to raise 1 gram of liquid water 1 degree C

water boils at 100 degrees C and water melts above 0 degrees C

1 kilojoules is 1000 joules

water's enthalpy of vaporization (steam) is 40.68 kJ/mol

a mole of water is 18.02 grams

we also have to assume the ice is at 0 degrees C

Step 1

Now start with your ice. The enthalpy of fusion for ice is calculated with this formula:

q = n x ΔH q= energy, n = moles of water, ΔH=enthalpy of fusion

Calculate how many moles of ice you have:

150g x (1 mol / 18.02 g) = 8.32 moles

Put that into the equation:

q = 8.32 mol x 6.02 = 50.09 kJ of energy to melt 150g of ice

Step 2

To raise 1 gram of water to the boiling point, it would take 4.18 joules times 100 (degrees C) or 418 joules.

So if it takes 418 joules for just 1 gram of water, it would take 150 times that amount to raise 150g to 100 degrees C. 418 x 150 = 62,700 joules or 62.7 kilojoules.

So far you have already used 50.09 kJ to melt the ice and another 62.7 kJ to bring the water to boiling. That's a total of 112.79 kJ.

Step 3

The final step is to see how much energy is left to vaporize the water.

Subtract the energy you used so far from what you were told you have.

265 kJ - 112.79 kJ = 152.21 kJ

Again q = mol x ΔH (vaporization)

You know you only have 152.21 kJ left so find out how many moles that will vaporize.

152.21 kJ = mol x 40.68 or mol = 152.21 / 40.68 = 3.74 moles

This tells you that you have vaporized 3.74 moles with the energy you have left.

Convert that back to grams.

3.74 mol x ( 18.02 g / 1 mol ) = 67.39 grams

5 0

2 years ago

Need some help, please. Explain why anions are always larger than the atoms from which they are derived, while cations are alway

ANTONII [103]

The question requires us to explain the differences in radii of neutral atoms, cations and anions.

To answer this question, we need to keep in mind that a neutral atom presents the same number of protons (positive particles) and electrons (negative particles). Another important information is that the protons are located in the nucleus of the atom, while the electrons are around the nucleus. Also, there is an electrostatic force between protons and electrons, which means that they the protons tend to attract the electrons to the nucleus.

While a neutral atom presents the same number of protons and electrons, a cation is an ion with positive charge, which means it has lost one or more electrons. In a cation, the balance between protons and electrons doesn't exist anymore: now, there is more positive than negative charge (more protons than electrons), and the overall attractive force that the protons have for the electrons is increased. As a result, the electrons stay closer to the nucleus and the radius of a cation is smaller than the neutral atom from which it was derived.

On the other side, anions present negative charge, which means they have received electrons. Similarly to cations, the balance between protons and electrons doesn't exist anymore, but in this case, there are more electrons than protons. In an anion, the overall attractive force that the protons have for the electrons is decreased. As a result, the electrons are "more free" to move and, as they are not so attracted to the nucleus, they tend to stay farther from the positive nucleus compared to the neutral atom - because of this, the radius of an anion is larger than the neutral atom from which it was derived.

3 0

1 year ago

Perform the following mathematical operation and express the results to the correct number of significant figures. (0.102 x 0.08

Kobotan [32]

Answer:

2.26

Explanation:

First you should know what are significant figures,

1 . All non - zero digits are significant.

2 . The zero between two non- zero are significant.Ex 302 has 3 significant figures.

3. The zero before the decimal and before any non-zero digit is non significant. Example : 0.003 has only 1 significant figure.

4. The zero after non zero are non - significant . But the zeros after the decimal point are significant.

300 has only 1 significant figure

300.0 has 4 significant figure

The least number of significant figures present in the number should be there in the final answer of the calculation.

Look at the number having minimum significant digits :

It is 3 (every number has 3- significant figures ) So the answer should also contain 3 - significant figures.

$\frac{0.102\times 0.0821\times 273}{1.01}$

First solve the numerator part

$\frac{2.285}{1.01}$

$=2.2635$

Round off this number to 3 significant figures.

Answer is = 2.26

It has 3 - significant digit since all the digits are non-zero.

5 0

3 years ago

I really need help with this. It’s #99 my work is not correct but I don’t know how to get the right answer can someone please he

Andrew [12]

Answer:

you are rigth

Explanation:

for the bottom you did extra credit

5 0

3 years ago

Explain what happens when an atom gains or looses an electron

lana [24]

When an atom gains an electron it becomes a negatively charged ion. When an atom looses an electron it becomes positively charged because the number of positively charged protons.

Hope this helps

3 0

3 years ago

Read 2 more answers