Answer:
F, S, Mg, Ba
Explanation:
Fluorine has a small atomic radius. These go up until Ba, which has a larger radius
Mass, air has that. Since what fills up a balloon? A gas
Shape, it has no definite shape. This one is accurate, it has no definite shape, it takes the shape of the object it's in.
Volume, does air take up space? If it does then yep. Balloon example/
Density, yes it does, because it's tightly wounded up.
D
Answer:
a metal spoon left in boiling water
Explanation:
First convert celcius to Kelvin.
20 + 273 = 293K
31 + 273 = 304K
Now we can set up an equation based on the information we have.
V1 = 5
P1 = 365
T1 = 293
V2 = 5
P1 = x
T2 = 304
The equation be: 
Now just solve.
1825/293 = 5x/304
Cross multiply.
554800 = 1465x
Divide both sides by 1465
x = 378.7030717 which can then be rounded to 378.7 mmHg
Two types of stoichiometry are; molar mass and coefficients from balanced equation.