Answer:
The reason why Newtons first law of motion is sometimes called the law of inertia is because it states that if the object is in motion, it will not rest unless an unbalanced force acts on the object.
Answer: 
Explanation:
According to ideal gas equation:

P = pressure of gas = 0.987 atm
V = Volume of gas = 12 L
n = number of moles = 0.50
R = gas constant =
T =temperature = ?


Thus the temperature of a 0.50 mol sample of a gas at 0.987 atm and a volume of 12 L is 
Answer:
621.2090000000001 grams
Explanation:
1 moles Calcium to grams = 40.078 grams
15.5*40.078 = 621.2090000000001 g
3k= 3 Potassium atoms
2S= 2 sulfur atoms
2O4= 8 oxygen atoms
The numbers in front of atoms are like coefficients(i.e. 2x or 3y). You should have 13 atoms in total.