IGCSE Chemistry Paper-1: Specimen Questions with Answers 90 - 92 of 99
Glide to success with Doorsteptutor material for Bank-PO : get questions, notes, tests, video lectures and more- for all subjects of Bank-PO.
Question 90
Question
MCQ▾As we move from left to right , what impact does it have on the atomic size of the elements.
Choices
| Choice (4) | |
|---|---|
a. | The atomic size increases |
b. | Atomic size remains the same. |
c. | The atomic size decreases |
d. | Atomic size variates |
Answer
c.Explanation
Atomic radius decreases from left to right within a period. This is caused by the increase in the number of protons and electrons across a period. One proton has a greater effect than one electron; thus, electrons are pulled towards the nucleus, resulting in a smaller radius.
Question 91
Question
MCQ▾How many isomers does butane have?
Choices
| Choice (4) | |
|---|---|
a. | 2 |
b. | 3 |
c. | 4 |
d. | 1 |
Answer
a.Explanation
Butane (C4H10) has two structural isomers.
Isomer 1 is the straight chain normal structure for butane (called n-butane) .
Isomer 2 (called 2-methylpropane) is a different structure with a branched chain which has a carbon atom joined onto three other carbon atoms.
Question 92
Question
MCQ▾In the following diagram, two nails are fixed on a cork and is placed in a beaker. The nails are connected to the two terminals of a battery through a bulb. When a substance X is poured in the beaker the bulb started to glow. What
Choices
| Choice (4) | |
|---|---|
a. | Glucose |
b. | Alcohol |
c. | Hydrochloric acid |
d. | Question does not provide sufficient data or is vague |
Answer
c.Explanation
Glowing of bulb indicates that there is a flow of current through the solution The electric current is carried through the solution by ions. Whereas alcohol and glucose does not conduct electricity.
Since the cation present in acids is H + , this suggests that acids produce hydrogen ions, H + (aq) , in solution, which are responsible for their acidic properties.