We are given the following equation:
y = y0 e^-0.0001216 t
where y = 1/5 y0, y0 is the original amount
So solving for time t:
1/5 y0= y0 e^-0.0001216 t
t = 13,235.51 years
So the human died about 13235.5 years ago
<h2>Answer:</h2><h3>The temperature of the gas: V</h3>
The temperature of gas is a variable quantity. It can be changed by changing energy or pressure of gas.
<h3>The amount of gas in the tube (in terms of mass and moles): C</h3>
It is a constant entity. As mass of gas once taken can not be changed by changing temperature, pressure etc.
<h3>The radius of the tube: C</h3>
The radius of tube cannot change at any rate.
<h3>The temperature of the gas (changed by the water surrounding it): V</h3>
It can be changed by changing the temperature of water surrounding it.
<h3>The type of gas: C</h3>
It can never be changed.
<h3>The pressure of the gas: V</h3>
It can be changed by simply changing temperature and volume of gas.
Answer: D) 140g
Explanation: no. of moles of NaCl = molarity X volume in litres = 2 X 1.2 = 2.4, and molar mass or mass of 1 mole of NaCl = 58.44 g, so 2.4 moles NaCl = 140.256 g
Answer:
31.78 grams
25.55%
Explanation:
The balanced reaction for ammonium chloride with calcium oxide will be:
2NH4Cl + Ca(OH)2 ---> CaCl2 + 2NH3 + 2H2O
The molecular weight for ammonium chloride(NH4Cl ) is 53.49g/mol, while the molecular weight for ammonium(NH3) is 17g/mol. The number of theoretical yield of ammonia from 100g of ammonium chloride will be:
100g / (53.49g/mol) * 2/2 * 17g/mol= 31.78 grams
If the actual yield is 8.12g, the percent yield will be: 8.12g/31.78g * 100% =25.55%
In the Southern Hemisphere this would be around June 20 and culminates on September 22.