From the graph. the answer is
A. supergiants
A mixture is composed of more than one substance combined
A pure substance cannot be decomposed in any reaction
<span>Both are considered types of substances
</span>hope it helps you playa!
Answer: 
atoms of hydrogen are there in
35.0 grams of hydrogen gas.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number 
of particles.
To calculate the moles, we use the equation:
1 mole of hydrogen 
= 
atoms
17.5 mole of hydrogen = 
atoms
There are atoms of hydrogen are there in
35.0 grams of hydrogen gas.
Answer:
= 374.90 kPa
Calculation:
As we know atm and kiloPascal are related to each other as,
1 atm = 101.325 kPa
So,
3.70 atm = X
Solving for X,
X = (3.70 atm × 101.325 kPa) ÷ 1 atm
X = 374.90 kPa
Using the ideal gas equation:
PV = nRT
Substituting n with mass / Mr
PV = mRT/Mr
Density = m/V
So rearranging:
Density = PMr/RT
P = 1 atm
R = 0.082 L atm / K mol
T = 273 K
Density = (1 x 80.6) / (0.082 x 273)
Density = 3.6 g / L
