Answer:
700g
Explanation:
Given parameters:
Density of gasoline = 0.7g/cm³
Volume of gasoline = 1L = 1000cm³
Unknown:
Mass of the gasoline = ?
Solution:
Density is the mass per unit volume of a substance. It can be expressed as;
Density = 
So;
Mass = density x volume
Mass = 0.7 x 1000 = 700g
KOH could serve as a reactant in a neutralization reaction
Answer:
1.3 M
Explanation:
The question asks to calculate the molarity of a solution.
We have to use the following equitation:
Molarity = # moles / 1 lt of solution
In this case we have a solution composed of 0.65 mol of NaF diluted in a total volume of 0.5 lt. We will have to do the following cross multiplication solving for x:
0.65 mol NaF / 0.5 lt = x mol NaF/ 1 lt
x = 1.3 mol NaF / 1 lt = 1.3 M
You'd use the temperature change equation. The specific heat of water is always 4.18J/(g °C).
Equation to use: q=mCΔT
21.8=(2.0)(4.18)(Tf-5)
21.8=(8.36)(Tf-5)
21.8/8.36=Tf-5
2.61=Tf-5
2.61+5=Tf
Tf=7.61 °C
Since you want to know how many °C it raises, you wouldn't pay attention to the last 2 steps, however if you need to know the final temp, you want to go to the last step.
O2 isn't necessary for rusting, but some source of oxygen is required. Rust is just another name for iron oxide, and without oxygen there can't be oxide.
Hope this helps,
Davinia.
