Answer:
Gas is sometimes measured in cubic feet at a temperature of 60 degrees Fahrenheit and an atmospheric pressure of 14.7 pounds per square inch. Gas production from wells is discussed in terms of thousands or millions of cubic feet (Mcf and MMcf). Resources and reserves are calculated in trillions of cubic feet (Tcf).
CaCl2
All of the other choices are elements
Answer:
2 significant figure is 13.1 aluminium
Answer:
1520 mmHg
Explanation:
Let's solve this by a factor conversion:
1 atm → 760 mmHg
2 atm . 760 mmHg / 1 atm = 1520 mmHg
Answer: The atomic weight of silver is 107.87 amu
Explanation:
Mass of isotope silver-107 = 106.91 amu
% abundance of isotope silver -107 = 51.84% = 
Mass of isotope silver-109 = 108.90 amu
% abundance of isotope silver-109 = 48.16% = 
Formula used for average atomic mass of an element :

![A=\sum[(106.91\times 0.5184)+(108.90\times 0.4816)]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%28106.91%5Ctimes%200.5184%29%2B%28108.90%5Ctimes%200.4816%29%5D)

Thus atomic weight of silver is 107.87 amu