Chemistry is the study of the substances that make up matter. It looks at their properties, how they react with each other, and how these reactions can create new substances.
-
Question 201: The difference between colloides and and suspensions is brought out clearly by the fact that while colloids?
Options:
A) do not scatter light, suspensions do
B) can be separated by filtration, suspension cannot be so separated
C) can be separated by a membrane, suspensions cannot
D) do not settle out on standing, suspensions do
Show Answer
The correct answer is D .
-
Question 202: Which of the following compounds gives a yellow residue when heated and also reacts with aqueous sodium hydroxide to give a white gelatinous precipitate soluble in excess sodium hydroxide solution?
Options:
A) (NH4)CO3
B) ZnCO3
C) Al2(SO4)3
D) PbCO3
Show Answer
The correct answer is B .
-
Question 203: In the reaction M + N P;∆H = + QKJ. Which of the following would increase the concentration of the product?
Options:
A) Decreaseing the concentration of N
B) Increasing the concentration of P
C) Adding a suitable catalyst
D) Decreasing the temperature
E) Increasing the temperature
Show Answer
The correct answer is E .
-
Question 204:
What is the valency of an element with the electronic configuration 2, 8, 7?
Options:
A) 7
B) 1
C) 2
D) 3
Show Answer
The correct answer is B .
-
Question 205: In what respect will two dry samples of nitrogen gas differ from each other if sample 1 is prepared by completely removing CO2 and O2 from air, and sample 2 is prepared by passing purified nitrogen(i)oxide over heated copper? sample 1 is
Options:
A) purer than sample 2
B) slightly denser than sample 2
C) in all respects the same as sample 2
D) colourless but sample 2 has a light brown colour
E) slightly less reactive than sample 2
Show Answer
The correct answer is B .
-
Question 206: The bond formed between two elements with electron configurations 1s2 2s2 2p6 3s2 and 1s2 2s2 2p4 is
Options:
A) metallic
B) covalent
C) dative
D) ionic
Show Answer
The correct answer is D .
-
Question 207:
H + OH HO
The equation above illustrates
Options:
A) precipitation
B) hydration
C) hydrolysis
D) neutralization
Show Answer
The correct answer is D .
-
Question 208: Which quantum number divides shells into orbitals?
Options:
A) principal
B) Arzimuthal
C) Magnetic
D) Spin
Show Answer
The correct answer is B .
-
Question 209:
Which of the following is a form of calcium carbonate?
I. limestone
II. marble
III. chalk
Iv. egg-shells
Options:
A) I only
B) I, II and IV
C) I and II only
D) I, II, III, and IV
Show Answer
The correct answer is D .
-
Question 210: The solution with the lowest pH value is
Options:
A) 5 ml of (m/10) HCL
B) 10 ml of (m/10) HCL
C) 15 ml of (m/5) HCL
D) 20 ml of (m/8) HCL
Show Answer
The correct answer is A .