Answer:
–36 KJ.
Explanation:
The equation for the reaction is given below:
2B + C —› D + E. ΔH = – 24 KJ
From the equation above,
1 mole of D required – 24 KJ of energy.
Now, we shall determine the energy change associated with 1.5 moles of D.
This can be obtained as illustrated below:
From the equation above,
1 mole of D required – 24 KJ of energy
Therefore,
1.5 moles of D will require = 1.5 × – 24 = –36 KJ.
Therefore, –36 KJ of energy is associated with 1.5 moles of D.
The gravitational force between the objects depends on the mass of the objects and the distance between them.
Answer:
5SiO2 + 2CaC2 ➡ 5Si + 2CaO + 4CO2
Explanation:
This question involves balancing the above equation. An equation is said to be BALANCED when all the atoms of each element in the reactant side equates that in the product side.
According to this question, a chemical reaction is given as follows: SiO2 + CaC2 = Si + CaO + CO2. Based on observation, the atoms of elements are Silicon, oxygen, calcium and carbon are not the same on the reactants and products side. Based on this, the balanced equation is:
5SiO2 + 2CaC2 ➡ 5Si + 2CaO + 4CO2
Answer:
7.35atm
Explanation:
Data obtained from the question include:
V1 = 28L
T1 = 42°C = 42 + 273 = 315K
P1 =?
V2 = 49L
T2 = 27°C = 27 + 273 = 300K
P2 = 4atm
Using P1V1/T1 = P2V2/T2, the original pressure can be obtained as follows:
P1V1/T1 = P2V2/T2
P1 x 28/315 = 4 x 49/300
Cross multiply to express in linear form
P1 x 28 x 300 = 315 x 4 x 49
Divide both side by 28 x 300
P1 = (315 x 4 x 49) /(28 x 300)
P1 = 7.35atm
Therefore, the original pressure is 7.35atm
Answer:
The new volume of the sample is halved.
Explanation:
Data obtained from the question include the following:
Initial volume (V1) = V
Initial temperature (T1) = T
Initial pressure (P1) = P
Final pressure (P2) = quadrupled = 4P
Final temperature (T2) = doubled = 2T
Final volume (V2) =?
Thus, we can obtain the new volume of the same by using the combined gas equation as shown below:
P1V1 /T1 = P2V2 /T2
P × V/T = 4P × V2/2T
Cross multiply
T × 4P × V2 = P × V × 2T
Divide both side by T × 4P
V2 = (P × V × 2T) / (T × 4P)
V2 = V/2
V2 = ½V
Therefore, the new volume of the sample is halved .
