Answer:

Explanation:
Given
31.8 moles of water
Required
Determine the number of molecule
In standard units: 1 molecule of water is:

Multiply both sides by 31.8



Express 191.4996 as a standard form

Apply law of indices:


Approximate:

Answer:
Block Y is heavier than Block X.
Explanation:
Answer:
THANKS SO MUCH
I actually did the same thin last week
Explanation:
A) Nitrogen has an ATOMIC mass number of 14, but nitrogen gas consists of N₂ molecules, so the mass to use in this problem is 28 g/mol. Rates of effusion ∝ 1/√(mass), so
<span>√(mass unknown) /√28 = (rate N₂ effusion)/(rate unknown effusion) = 1.59 </span>
<span>∴ mass unknown = (1.59)²(28) = 70.78 g/mol </span>
<span>B) One possible gas that comes close for this mass is NF₃.</span>
Answer:
The electronegativity of carbon (EN = 2.55) is too small to allow carbon to form C4- ions with most metals and too large for carbon to form C4+ ions when it reacts with nonmetals. Carbon therefore forms covalent bonds with many other elements.