Science

1.What's the equation for kinetic energy?

2.Fill in gaps:

Force x _____________=0.5 x___________xspeed____

Therefore, the ___________ done equals the ______________ energy.

3. Fill in the gaps: When a car's speed _____________, its kinetic energy is ______________ because of the ______________ part in the equation. This means that the work done by the brakes will be ________________. Since work= force x __________ the braking ______________ will be _____________.

4.Name 4 factors that fuel consumption depends on.

5.How can an electric car be said to be polluting?

1. 0.5 x mass x velocity(squared)

2. distance; mass; squared; work; kinetic

3.doubles; quadrupled; v^2; quadrupled;distance; distance;quadrupled

4.energy required to increase kinetic energy

energy required to work against friction

driving style and speed

road conditions

5.It can be said to be polluting as fossil fuels are needed to charge their batteries to produce electricity.

1.What do halogens produce when they react with alkali metals? Also, give an example with a reaction between Lithium and Chlorine(a word and symbol equation)

2.At the top of elements in the periodic table they become more reactive as you go down they are less reactive. Why are they more reactive?

3a.Fill in the gaps: A _______reactive halogen will displace a _______reactive one.

b.Potassium __________+Chlorine----> Potassium___________+Bromine

c.2Kl+Cl2---->_________+___

4.Why do all the halogens have similar properties?

5.Reduction is _________ of electrons.

1. To form metal halides: Lithium + Chlorine-----> Lithium Chloride 2Li+Cl2--->2liCl

2.They are more reactive because the outer shell is closer to the nucleus-it is easier to gain an electron.

3a.more reactive halogen will diplace a less reactive one

b.potassium bromide+chlorine--->potassium chloride+bromine

c.2Kl+Cl2--->2KCl+I2

4.They have similar properties because when they react, atom gains 1 electron to form a negative ion with a stable electronic structure.

5.Reduction is gain of electrons

Clouds of dust and gas pulled together by gravity-NEBULA---->Hydrogen atoms are pulled together at high speeds causing heat. When the temperature is high enough, thermonuclear fusion happens-PROTOSTAR---->Fusion of hydrogen to produce helium and energy for heat and light---->Hydrogen runs out and star swells and cools

FOR MEDIUM WEIGHT STARS---->RED GIANT---->Star conducts and becomes very dense---->WHITE DWARF----->Star no longer emits heat and light-BLACK DWARF

FOR HEAVY WEIGHT STARS--->SUPERGIANT--->SUPERNOVA-Enormous axplotion heavier elements thrown into space

EITHER:Protons and electrons crush together to from the most dense object known-NEUTRON STAR

OR:Huge gravitational pull. NOT even light can escape BLACK HOLE