When a chemical change happens we sometimes see a colour change. What other observations tell you that a chemical change is happening?

A heavy object and a light object in a vacuum are dropped at the same time from rest. The heavy object reaches the ground later than the light object. at the same time as the light object. sooner than the light object.

Mix 4 L of 30°C water is 6 L of 40°C water and you'll have water at what temperature?

A 35.2-g sample of an alloy at 93.0°C is placed into 219 g of water at 22.0°C in an insulated coffee cup. Assume that no heat is absorbed by the cup. If the final temperature of the system is 31.

Star x has twice the mass of the sun

Aristotle, the ancient Greek philosopher, thought that heavy objects fall to Earth faster than lighter objects. How could Aristotle's hypothesis be supported or disproved?

What is the speed of a 50 g rock if its de Broglie wavelength is 3.32 x 10?

The difference between newtons first law of motion and newtons third law of motion

A sound wave traveling at STP has a period of. 0023 seconds. The wavelength of this sound is closest to 1) 1.4E5 2) 6.9E-6 3) 0.76m 4) 76m

Static charge develops on a substance as it acquires or loses protons due to friction. a. True b. False

A milk truck carries milk with density 64.6 lb/ft3 in a horizontal cylindrical tank with diameter 12 ft. (a) Find the force exerted by the milk on one end of the tank when the tank is full. (Round your answer to the nearest integer.) lb