IGCSE Chemistry: Specimen Questions with Answers 226 - 228 of 240
Question number: 226
Question
Water reacts with metallic oxide to give ________.
Choices
| Choice (4) | Response | |
|---|---|---|
| a. | Acid |
|
| b. | Neutral Product |
|
| c. | Water |
|
| d. | Base |
|
Answer
d.Explanation
Water reacts with metallic oxide to give base.
For example, water reacts with potassium oxide to give potassium hydroxide .
Question number: 227
Write in Short
Classify each of the following as either an element, compound or mixture.
Copper (1 Marks)
Explanation
Copper is a chemical element with symbol Cu (from Latin: cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a reddish-orange color.
Question number: 228
Write in Short
A student followed the course of this reaction by measuring the volume of oxygen released over a period of time.
The diagram below shows some results that he obtained using hydrogen peroxide at three different concentrations.
Image of Hydrogen Peroxide
Image of hydrogen peroxide
-
Describe how the concentration of hydrogen peroxide affects the rate of this reaction.
…………………………………………………………………………………………………
Explanation
Concentration of Hydrogen per oxide affect the reaction by increasing the rate of reaction the hydrogen per oxide will be concentrated then time taken to complete the reaction will be less. Data is given below.
Concentration of Hydrogen
Concentration of Hydrogen