Answer:

Explanation:
Density can be found by dividing the mass by the volume.

The mass of the water is 50.0 grams.
The volume of the water is 50.0 milliliters.

Substitute the values into the formula.

Divide.

The density of the water is 1.0 grams per milliliter. Also, remember that the density of pure water is always 1.0 g/mL or g/cm³
Answer:
Explanation:
Pair 2.50g of O₂ and 2.50g of N₂
The atoms sample with the largest number of moles since the masses are the same would be the one with lowest molar mass according the the equation below:
Number of moles = 
Atomic mass of O = 16g and N = 14g
Molar mass of O₂ = 16 x 2 = 32gmol⁻¹
Molar mass of N₂ = 14 x 2 = 28gmol⁻¹
Number of moles of O₂ =
= 0.078mole
Number of moles of N₂ =
= 0.089mole
We see that N₂ has the largest number of moles
Answer: 7
Explanation:
Before a number but after a decimal. The zeros at the end would usually mean that it doesn't count but since the numbers are before the zeros and after a decimal it's 7 sig figs