The <span>equations that has the correct formulas and also is a balanced equation are:
</span>2Be + O2 - > 2BeO
<span>Mg + O2 - > MgO2
</span>The answer are letters C and D. The rest of teh choices are not balanced chemical equations.
Answer: The empirical formula will be 
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of S= 3.21 g
Mass of F = 11.4 g
Step 1 : convert given masses into moles.
Moles of S =
Moles of F =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For S= 
For F = 
The ratio of S: F= 1: 6
Hence the empirical formula is
For a mole of P4O10, there are 4 moles of P. Hence for 76 moles of P4O10, the number of P moles is a total of 304.
Answer: D. sugar dissolves when placed in water.
Why:
Chemical properties/changes produce NEW substances.
So when sugar dissolves in water, it breaks down, but NOT to a chemical level that separates its elements. Therefore, it would still be sugar and will not create a new compound/element.
This results in the conclusion that when sugar dissolves in water, it is a physical property, NOT chemical.
<span>Water has a Mol.mass of 18g/mol. (2 x 1:H) + (1 x O:16) = 18.
Mass / mol.mass = moles.
3.45g / 18g/mol. = 0.192 moles of sweat.
0.192mol. x 44.0kJ/mol = 8.43kJ of heat released from the body.</span>
