Weight & Mass
5 grams of salt are added to 40 grams of water in a cup that is 35 grams. What will the total weight of the cup be?
80g
Cracking an egg is an example of what kind of change?
Physical Change
Anything that takes up space and has mass/weight.
Any type of metal.
Conductor
What happens to most substances when they are heated?
They expand.
True or False:
Freezing water causes it to become heavier since solids weigh more than liquids.False.
The ice would weigh the same of the water.
Changes in an substance's state of matter is an example of what kind of change (ex: water freezing into ice, water evaporating into water vapor)?
Physical Change
A substance that blocks/slows down the flow of energy.
Insulator
Clothing.
Insulator
True or False:
When you step outside in the winter, your body cools down because cold energy from the air is being transferred to you.False.
Your body cools down because it is losing heat as it is transferred to the air.
100 grams of pancake mix and 30 grams of water ar gathered to make pancakes. What will be the total weight of the ingredients BEFORE they are mixed?
130g
Describe the difference between a physical and chemical change.
Physical- Properties change but no new substance is made
Chemical- New substance is made
Qualities that can be used to describe an object/substance
Properties
Describe the difference between a conductor and insulator
Conductors- allow the easy flow of energy
Insulator- does not allow easy flow of energy.
How is heat always going to move between two objects?
From the warmer object to the colder objects
If pot of water is put on a stove to boil without a lid. What would happen to the weight of the pot?
It would decrease as water evaporates out.
A student mixes two substances together and they observe that it starts putting off a sour smell. What kind of change took place? How do you know?
Chemical
New odor is a sign a new substance has been made
Any object that has its own specific qualities.
Substance
You are asked to stir hot soup that is on the stove. You see a metal spoon and a wooden spoon on the counter.
Which one should you use? Why
Wooden spoon.
It will block heat from moving to your hand
What would happen to a full water bottle that is placed in a freezer overnight?
The water would expand and bust the bottle.
78 pounds of firewood was burned in a furnace to heat a building one night. The next morning, there were only 43 grams of ash in the furnace. Why is the ash lighter than the wood originally was.
Some of the wood turned into gases and spread out/escaped the furnace.
List 3 signs of evidence that show when a new substance has been made
-Heat made
-New color made
-Bubbles/Foam made
Variables.
To help keep heat from moving through the house.
This will keep heat in the house in the winter
And will keep heat out of the house in the summer
Explain why it is important the engineers put spaces between sections of a metal bridge when building.
To make room for the metal to expand and contract so that it does not bend/break.