Chapter 5 grade 9

How to test the presence of oxygen?

Put a _______splint at the mouth of test tube

What is the salt formed for citric acid?

Which statement will not happen when the reaction has finished ?

• bubble produce/effervescence

• Colour of universal indicator changes

• Solid product forms

• Solid reactant dissapear

• None of above

pH meter that shows a value of 7 means

Zn+2HCl → _____+H₂

Which of the pH value is strongly alkali?

• 2-4

• 8-10

• 11-14

• 0-2

• None of them

Def. of exothermic reaction

• Energy released to surrounding to FORM NEW BOND in product

• Energy absorbed from surrounding to BREAK BOND in reactant

• None of them

Which is the most reactive metal?

• Potassium

• Lithium

• Sodium

• Calcium

• Magnesium

Zinc+lead nitrate→

What is this process?

Step1:heat the solution untill you see crystal forming

Step2 : Remove the heat and let water evaporate to form salt crystal

*To form large salt crystal,let solution evaporate slowly