The answer is d) 0.862 mm
Answer:
Explanation:
A 'mole' is the mass of substance that contains 1 Avogadro's Number of particles of that substance. This is equal to 1 formula weight of the substance. That is when thinking 'moles', think 'how many formula weights are there in the given mass?'
Example.
Given 100 grams of water (H₂O => formula weight = 18 grams/mole) ...
Ask 'how many 18's are there in 100?' => number of moles of H₂O... => 100/18 = 5.555... moles H₂O
This is the same for any substance => how many formula weights are there in the GIVEN mass? Always => #moles.
moles = mass(g)/formula wt(g·mol⁻¹)
Answer:
0.948g
Explanation:
Atomic mass of Mg is 24.305
1 mole of Mg is therefore 24.305 g
0.039 moles will weigh 0.039 x 24.305 g/mole = 0.948 g
Answer:
The water molecules have kinetic energy to begin with, but not enough to boil in the presence of air pressure. When we remove the air pressure, the most energetic water molecules become water vapor gas.