Chemistry 2015 | Study Mode

Question 41
A
positive change
B
negative entropy change
C
no entropy change
D
a minimum entropy change
Explanation
No entropy change because the sugar will not change the chemical equivalent of the tea. Options A,B,D are not appropriate because they will change the chemical combination of the tea

Question 42
A
positive
B
zero
C
negative
D
intermediate
Explanation
Entropy s is a measure of the degree of disorder or randomness of a substance. The entropy charge in the system is negative. Options B, C, D will not give negative but the result into positive

Question 43
A
soluble
B
C
cheaper
D
foamy
Explanation
Biodegradable because the straight hydrocarbons are natural and slightly soluble in water. Options A,C,D do not have strength hydrocarbon chains and they could harm the environment if they are made with the detergent

Question 44
A
B
particulate matter
C
oxides of carbon
D
gaseous hydrocarbon
Explanation
Oxide of sulphur is formed as a result of acid rain. Options A,B, D are not formed as a result of the pressure of acid

Question 45
A
calcium tetraoxosulphate (IV)
B
calcium hydrogentrionocarbonate (IV)
C
calcium hydroxide
D
calcium trioxocarbonate (IV)
Explanation
Calcium hydrogen trionocarbonate (iv) will cause the forming of kettles whenever water is present. Options A, C, D will not react under the presence of water

Question 46
A
oxygen is consumed
B
heat is supplied
C
the reversible process occurs
D
a new substance is formed
Explanation
In chemical change a new substance is formed while in physical change no new substance is formed. Options A,B,C are all properties of a physical change

Question 47
A
decrease
B
increase
C
remain constant
D
be zero
Explanation

Question 48
A
Decelerate the reaction
B
Increase yield of Pcl3
C
Increase the yield of Pcl5
D
Accurate the reaction
Explanation
If we decrease the pressure in the reaction, there will be rapid breakage spilling of pcl5. And these follows a principle that molecule of gases tends to move from a region of higher pressure to low pressure. Option A,C,D will not be affected by pressure decrease

Question 49
A
AlCl3
B
NH4Cl
C
Na2CO3
D
CH3COONa
Explanation
AlCl3 will give a precipitate when treated with solution. Option B,C,D will not give a precipitate when treated with NaOH solution

Question 50
A
$$1s^2 2s^2 2p^6 3s^2 3p^1$$
B
$$1s^22s^2 2p^4 3p^1 3s^1$$
C
$$1s^2 2s^2 2p^6 3s^2 3p^3$$
D
$$1s^1 2s^2 2p^6 3s^2 3p^4$$