Which will speed up a chemical reaction?

A.

Apply heat.

B.

Increase the concentration of the reactants.

C.

Grind up the substance, so there is more surface area.

D.

all of the above

Circle the item (s) which are properties of a system: (A) Shaft work (B) Temperature (C) Volume (D) Heat (E) None of the above

Jake boils some water to make a cup of tea. He uses a 5 kW kettle that takes 2 minutes to boil the water. a) Calculate how much energy Jake used, in kWh, to boil the water. Show your working.

an egg is dropped from the top of the library roof. then 2.2 seconds after that a second egg is thrown straight down with an initial speed of 58m/s. it is then observed that the two eggs splat on the ground at the same instant.

How do Earth's shape, orbit and the tilt of its axis determine the seasons?

Consider a current carrying a wire coming out of your computer screen towards you. Which statement below correctly describes the magnetic field created by the current in the wire? 1.

Exoplanets (planets outside our solar system) are an active area of modern research. Suppose you read an article stating that there is a newly discovered planetary system with three planets.

A car with a mass 1200 kg accelerates at 1.89 m/s2. What is the total force exerted by the car on the road (answer in N to two decimal places) ?

How Long will it take a plane flying north from Miami to reach New York City 1800 km away if the average velocity of the plane is 940 km/h

If vector A = 5.5N NE and vector B = 10m N 30° W, what is the vector product of A*B

Which is the best desciption of a molecule?