Composite materials Flashcards
1
Q
what are composite materials
A
composite materials are combinations of two or more materials with some properties each.
2
Q
what is concrete made of
A
it is made from a mixture of cement, sand, aggregate(crushed rocks), and water.
3
Q
what are some properties of concrete and where is it used in
A
string hardwearing and easily moulded it is used in roads, bridges and buildings.
4
Q
what is an endothermic reaction
A
it means that it absorbs energy from its surroundings
5
Q
what is an exothermic reaction
A
during exothermic changes, energy is transferred to the surroundings, so their temperature rises.
6
Q
what happens as concrete sets
A
it gets warmer due to exothermic reactions. the heat can cause the concrete to expand and crack.
