1) D = 13.6 g / mL
2)ethyl alcohol weighs 158g
3)ρ
_copper = 8.9 g 
Explanation:
1)
D = m / V
=306.0 g / 22.5 mL
D= 13.6 g / mL
2)
density = mass / volume
mass = density × volume
=0.789g /ml × 200.0 ml
M=158g
Ethyl alcohol weighs 158g
3)
ρ (density) = Mass / Volume
ρ
_copper = 1896 g / 8.4cm × 5.5cm × 4.6cm
= 1896g / 212.5 
ρ
_copper=8.9 g 
When soda companies add carbon dioxide gas to a soda mixture, the water is very cold so it can hold a lot of gas. They also use pressure to put more gas in the water than it could normally hold at that temperature.
But when a soda can warms up a bit or when the can is shaken, that extra gas is really ready to come out. So when you open up the can and release the pressure, splooosh!
Answer:
Reagent O₂ will be consumed first.
Explanation:
The balanced reaction between O₂ and C₄H₁₀ is:
2 C₄H₁₀ + 13 O₂ → 8 CO₂ + 10 H₂O
Then, by reaction stoichiometry, the following amounts of reactants and products participate in the reaction:
- C₄H₁₀: 2 moles
- O₂: 13 moles
- CO₂: 8 moles
- H₂O: 10 moles
Being:
- C: 12 g/mole
- H: 1 g/mole
- O: 16 g/mole
The molar mass of the compounds that participate in the reaction is:
- C₄H₁₀: 4*12 g/mole + 10*1 g/mole= 58 g/mole
- O₂: 2*16 g/mole= 32 g/mole
- CO₂: 12 g/mole + 2*16 g/mole= 44 g/mole
- H₂O: 2*1 g/mole + 16 g/mole= 18 g/mole
Then, by reaction stoichiometry, the following mass quantities of reactants and products participate in the reaction:
- C₄H₁₀: 2 moles* 58 g/mole= 116 g
- O₂: 13 moles* 32 g/mole= 416 g
- CO₂: 8 moles* 44 g/mole= 352 g
- H₂O: 10 moles* 18 g/mole= 180 g
If 78.1 g of O₂ react, it is possible to apply the following rule of three: if by stoichiometry 416 g of O₂ react with 116 g of C₄H₁₀, 62.4 g of C₄H₁₀ with how much mass of O₂ do they react?

mass of O₂= 223.78 grams
But 21.78 grams of O₂ are not available, 78.1 grams are available. Since you have less mass than you need to react with 62.4 g of C₄H₁₀, <u><em>reagent O₂ will be consumed first.</em></u>
An atom cannot be broken down any smaller whereas a compound is made up of atoms and can be broken down into smaller pieces (the individual atoms that make it up)
Hope this helps!