Answer:
The greatest acceleration when the unbalanced force is applied will be experienced in :
A) The box with a mass of 2 kg
Explanation:
According to second law of motion the external unbalanced force is directly proportional to rate of change of momentum.
F = (Final momentum - initial momentum)/time
or
Force is equal to the product of mass and acceleration
F = m x a
Here a= acceleration
m = mass of the object
If Force is constant then acceleration is inversely proportional to mass
A) The box with a mass of 2kg
F = 8 N
a = 4 m/s2
B) The box with the mass of 4kg
a = 2 m/s2
C) The box with a mass of 6kg
a = 1.33 m/s2
D) The box with a mass of 8kg
a = 1 m/s2
Explanation:
I
have not yet learnt chemistry so sorry
They all have the same number of electrons in the electron cloud.
Conducters e.g gold copper silver
Answer:
The percent by mass of copper in the mixture was 32%
Explanation:
The ammount of HNO₃ used is:
mol HNO₃ = volume * concentration
mol HNO₃ = 0.015 l * 15.8 mol/l
mol HNO₃ = 0.237 mol
According to the reaction, 4 mol HNO₃ will react with 1 mol Cu and produce 1 mol Cu²⁺. Since we have 0.237 mol HNO₃, the amount of Cu that could react would be (0.237 mol HNO₃ * 1 mol Cu / 4 mol HNO₃) 0.06 mol. This reaction would produce 0.060 mol Cu²⁺, however, only 0.010 mol Cu²⁺ were obtained, indicating that only 0.010 mol Cu were present in the mixture. This means that the acid was in excess, so we can assume that all copper present in the mixture has reacted.
Since 0.010 mol of Cu²⁺ were produced, the amount of Cu was 0.01 mol.
1 mol of Cu has a mass of 63.5 g, then 0.01 mol has a mass of:
0.01 mol Cu * 63.5 g / 1 mol = 0.635 g.
Since this amount was present in 2.00 g mixture, the amount of copper in 100 g of the mixture will be:
100 g(mixture) * 0.635 g Cu / 2 g(mixture) = 32 g
Then, the percent by mass of Cu (which is the mass of Cu in 100 g mixture) is 32%
