The answer is the el second one since it is a physical change
To convert weight to moles, we must use the molar weight found on the periodic table. Sulfur's (S) molar weight is 32.06 g/mol. Then we set up an equation and cancel out units:
So now we know that 0.994g of sulfur is equal to 0.031 moles.
Answer:
CO.
Explanation:
Assuming the given percentages are by mass, we can solve this problem via imagining we have <em>100 g of the compound</em>, if that were the case we would have:
Now we <u>convert those masses into moles</u>, using the<em> elements' respective molar masses</em>:
- 42.9 g of C ÷ 12 g/mol = 3.57 mol C
- 57.1 g of O ÷ 16 g/mol = 3.58 mol O
As the number of C moles and O moles is roughly the same, the empirical formula for the compound is <em>CO</em>.
Answer:
Explanation:
Firstly, it should be noted that melting and freezing points are the same. Thus, when a substance melts at a certain temperature, it means it can also start freezing/solidifying at that same temperature. That been said, <u>when the substance P is a solid at a certain temperature, the other compound Q will boil at that same temperature and hence will be a gas at that same temperature</u>.
Answer:
Explanation:
Here's where all that equation balancing is going to come into use. Since the main object of the question is not the equation, I'm just going to balance it and use it.
4Fe + 3O2 ====> 2Fe2O3
Step One
Find the number of mols of O2 in 24.9 grams of O2
1 mol O2 = 2*16 = 32 grams
x mol O2 = 24.9 grams Cross multiply
32x = 24.9 * 1 Divide by 32
x = 24.9/32
x = 0.778 moles of O2
Step Two
Type the findings under the balanced equations parts. Solve for the number of moles of Fe
4Fe + 3O2 ====> 2Fe2O3
x 0.778
Step Three
Set up the proportion
4/x = 3/0.778 Cross multiply
Step Four
Solve the proportion moles of Fe
4*0.778 = 3x
3.112 = 3x Divide by 3
3.112/3 = 3x/3
x = 1.037 moles of Fe
Step Five
Find the mass of Fe
1 mol Fe = 56 grams
1.037 mol Fe = x Cross Multiply
x = 56*1.037
x = 58.1 grams
