STAAR Unit 1 and 2 lab safety and matter

Which best describes the change in salt grains as they dissolve in water?

• The grains change their chemicals until they become water.
• The grains get higher in temperature until they melt into a liquid.
• The grains get smaller in size until they can no longer be seen.
• The grains are washed clean until they are perfectly clear.

Which mixture could be separated using a magnet

• pepper and sugar
• pebbles and marbles
• sand grains and seashells
• iron filings and pepper 

Some girls use a curling iron to fix their hair. It is very hot when plugged in for a while. If you want to protect you skin, you would need to pick it up on the plastic end. Which property of the plastic is important for it to be used on a curling iron?

• soluble in water
• insulates thermal energy
• conducts electrical energy
• emits magnetic energy 

If a thermometer reads 36 degrees Celsius how many more degrees will the water have to cool to reach the freezing point?

• 4
• 32
• 36
• 0

If a substance is soluble in water it will ....

• fall to the bottom of the container
• float on the top
• no longer be visible

What is the freezing point in degrees Celsius of water

• 0
• 32
• 36
• 40

What is the boiling point of water in degrees Celsius?

• 100
• 0
• 32
• 36

Lab Apron
Safety Goggles
Protective Gloves
are all examples of 

• Lab tools
• safety equipment
• science uniforms
• measurement devices

Which of the following material choices would be best in conserving resources while doing an investigation 

• clear, glass beaker that can be washed and reused
• clear, plastic cup that can be recycled in the school recycling program
• ceramic mug that can be washed
• clear, plastic sandwich bag that can be thrown away 

Which of the following is soluble in water 

• pebbles and sand in water 
• sand in water
• salt in water
• iron in water