D. How the pull of gravity has changed.
Answer:
Explanation:
a )
m = m₀ 
m is mass after time t . original mass is m₀ , λ is disintegration constant
λ = .693 / half life
= .693 / 1590
= .0004358
m = m₀ 
b )
m = 50 x 
= 40.21 mg .
c )
40 = 50 
.8 = 
= 1.25
.0004358 t = .22314
t = 512 years .
Molar mass C6H12O6 = 12 x 6 + 1 x 12 + 16 x 6 = 180 g/mol
1 mole ------------ 180 g
( moles ) --------- 843.211 g
moles = 843.211 x 1 / 180
moles = 843.211 / 180
= 4,684 moles of C6H12O6
69 mmHg pressure is exerted by oxygen if 40% of the gas pressure is exerted by the oxygen gas.
<h3>What is pressure?</h3>
Pressure is defined to be the amount of force exerted per area
40% of pressure is exerted by oxygen gas.
So, 60% of pressure will be exerted by carbon dioxide gas.
60% of 115 mmHg = 69 mmHg
Hence, 69 mmHg pressure is exerted by oxygen if 40% of the gas pressure is exerted by the oxygen gas.
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