IGCSE Chemistry: Specimen Questions with Answers 97 - 99 of 240

Doorsteptutor material for Bank-PO is prepared by world's top subject experts: get questions, notes, tests, video lectures and more- for all subjects of Bank-PO.

Question 97

Write in Short

Short Answer▾

A sealed tube containing an equilibrium mixture of nitrogen dioxide and dinitrogen tetroxide was placed in a beaker of ice cold water. The color of the mixture changed from brown to pale yellow.

Is the forward reaction exothermic or endothermic? Give an explanation for your choice.

Explanation

Type of this reaction is exothermic because when this reaction happens then 57.2 J

Sulfuric acid and malonic acid are both dibasic acids. One mole of a dibasic acid can form two moles of hydrogen ions.

Question 98

Edit

Write in Short

Short Answer▾

How could you determine if a sample of malonic acid is pure?

result if pure [2 Marks]

Explanation

If malonic acid is pure then it starts melting else it will not.

Question 99

Question

MCQ▾

Element X is represented by

Which statement about element X is correct?

Choices

Choice (4)

a.

An atom of X contains protons and neutrons

b.

An atom of X contains protons and electrons

c.

X forms an ion by gaining electrons

d.

X is placed in Group III of the Periodic Table

Answer

d.

Explanation

Correct option is D because X represent Aluminium and In periodic table Aluminium is placed in group III.

Its atomic number is and It is a silvery-white, soft, nonmagnetic, ductile metal in the boron group. As shown in figure.

Periodic Table

Developed by: