Conductivity and Melting Points Quiz

What is the main function of the conductivity tester described in the video?

• To test the brightness of a light bulb

• To determine the melting point of substances

• To measure the temperature of substances

• To check the conductivity of substances

What must be true for the light bulb in the conductivity tester to light up?

• The light bulb must be unplugged

• The leads must be connected by a conductive material

• The circuit must be incomplete

• The leads must be disconnected

Which substance was tested first for conductivity?

• KCl

• Glucose

• KI

• HCl

What is the purpose of adjusting the Bunsen burner to allow more oxygen in?

• To decrease the flame temperature

• To increase the flame temperature

• To change the color of the flame

• To make the flame safer

What is the significance of the inner blue cone in the Bunsen burner flame?

• It is the safest part of the flame

• It is used to measure the flame's height

• It is the hottest part of the flame

• It indicates a cooler part of the flame

Which substance did not melt even after 80 seconds of heating?

• Glucose

• KCl

• Paraffin

• Benzoic acid

What was observed when KNO3 was heated?

• It did not melt

• It turned into a gas

• It started to melt and became liquid

• It exploded

What was the result of heating paraffin?

• It remained solid

• It melted and much of the wax became liquid

• It turned into a gas

• It did not melt

Why was acetic acid not tested for melting?

• It is too dangerous to heat

• It reacts with the crucible

• It is already a liquid at room temperature

• It is a solid at room temperature

Which substance was not tested for melting because it is a gas at room temperature?

• Paraffin

• HCl

• Benzoic acid

• KNO3