Answer:

Explanation:
We need to use the formula for heat of vaporization.

Identify the variables.
- The heat absorbed by the evaporating water is the <u>latent heat of vaporization. </u>For water, that is 2260 Joules per gram.
- Q is the energy, in this problem, 50,000 Joules.
- m is the mass, which is unknown.

Substitute the values into the formula.

We want to find the mass. We must isolate the variable, m.
m is being multiplied by 2260 J/g. The inverse operation of multiplication is division. Divide both sides by 2260 J/g.


Divide. Note that the Joules (J) will cancel each other out.


Round to the nearest whole number. The 1 in the tenth place tells us to leave the number as is.

The mass is about 22 grams, so choice B is correct.
Answer:
D
Explanation:
One of the properties of metals is their abilities to form a stable compounds by losing electron(s). Metals form positive ions (cations) when they lose electron(s).
1 molecule of C3H7O has 7 atoms of hydrogen (remember that the numbers to the right of each symbol ara subscripts and they indicate the number of atoms of that element in the molecular formula).
Then 5 molecules will have 5 * 7 atoms of hydrogen.
5 * 7 = 35.
Then the answer is that there are 35 atoms of hydrogen in 5 molecules of isopropyl alcohol, C3H7O
According to the illustration, the vanadium (V) oxide would be a catalyst.
<h3>What are catalysts?</h3>
Catalysts are substances that are utilized in reactions that are not themselves consumed in reactions but only speed up the rate of the reactions.
Catalysts speed up the rate of reactions by lowering the activation energy of the reactants.
Sulfur dioxide reacts with oxygen to produce sulfur trioxide. The vanadium (v) oxide is not consumed in the reaction. Thus it only serves as a catalyst.
More on catalysts can be found here: brainly.com/question/12260131
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