1.
V = 200 mL (volume)
c = 3 M = 3 mol/L (concentration)
First we convert mL to L:
200 mL = 0.2 L
Then we calculate the moles using the formula: n = V × c = 0.2 L × 3 mol = 0.6 mol
Finally, we just use the molar mass of CaF2 to calculate the actual mass:
molar mass = 78 g/mol
The formula is: m = n × mm (mass = moles × molar mass)
m = 0.6 mol × 78 g/mol = 46.8 g
2.
For this question the steps are exactly like the first question.
V = 50mL = 0.05 L
c = 12 M = 12 mol/L
n = V × c = 0.05 L × 12 mol/L = 0.6 mol
molar mass (HCl) = 36.5 g/mol
m = n × mm = 0.6 mol × 36.5 g/mol = 21.9 g.
3.
The steps for this question are the opposite way.
m(K2CO3) = 250 g
molar mass = 138 g/mol
n = m ÷ mm = 1.81 mol
c = 2 mol/L
V = n ÷ c = 1.81 mol ÷ 2 mol/L = 0.905 L = 905 mL
Answer:
433 m
Explanation:
Since the fall represents motion under gravity, we use the equation
s = ut - 1/2gt² where s = height of cliff or distance bowling ball falls through, u = initial velocity of bowling ball = 0 m/s(since it starts from rest), t = time = 9.4 s and g = acceleration due to gravity = -9.8 m/s².
So, substituting the values of the variables into the equation, we have
s = 0 m/s × 9.4 s - 1/2 × 9.8 m/s² × (9.4 s)²
s = 0 m - 1/2 × -9.8 m/s² × 88.36 s²
s = 1/2(865.928 m)
s = 432.964
s ≅ 433 m
Molecules in a gas will have more movement than molecules in a solid. This is because the molecules in solid matter are packed very tightly together to maintain its shape, whereas with gases they are spaced much further apart and fairly free to move. Hope this helps!
I don't know the answer. Can I ask your help to answer that question? pls.
Answer:
I think it is mixture and of chemical reaction
