Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
<u>Answer:</u> The solubility of oxygen at 682 torr is 
<u>Explanation:</u>
To calculate the molar solubility, we use the equation given by Henry's law, which is:

Or,

where,
are the initial concentration and partial pressure of oxygen gas
are the final concentration and partial pressure of oxygen gas
We are given:
Conversion factor used: 1 atm = 760 torr

Putting values in above equation, we get:

Hence, the solubility of oxygen gas at 628 torr is 
Answer:
our bodies will dehydrate causing us to die a dreadfully excruciating painful death
Answer:
8
Explanation:
1 mole = 6.02 × 10²³ atoms
? moles = 4.816 × 10²⁴ atoms.
? Moles = 4.816 × 10²⁴ ÷ 6.02 × 10²³
? Moles = 8 moles
8 moles of aluminum = 4.816 × 10²⁴
<span>The water cycle is like a big circle and doesn’t really have a starting point. There are 4 main stages involved in water cycle i.e. evaporation, condensation, precipitation and runoff, so, I'd say you become water, you evaporate, then you turn into a cloud and rain, then runoff.</span>