Round off each of the following numbers to two significant figures:

(a) 0.436

(b) 9.000

(c) 27.2

(d) 135

(e) 1.497 X 10-3

(f) 0.445

What type of elements make up an ionic compound

Light from the sun transfers solar energy to the earth system. Sunlight travels to earth as

A large crystal of potassium manganate is placed in the bottom of a beaker of cold water, and left for several hours. Describe what would be seen after 5 minutes

How many types of nomenclature in the features of organic chemistry? What are they?

What is the value for º for the following reaction, given the standard entropy values? Al2O3 (s) + 3H2 (g) → 2Al (s) + 3H2O (g) -35 J/mol·K +35 J/mol·/K +179 J/mol·K -179 J/mol·K

The water level in a graduated cylinder stands at 20.0 ml before and at 26.2 ml after a 16.74 g metal sample is lowered into the cylinder. what is the density of the sample. what metal is the sample most likely to be

What are the tube feet on a star fish

What kingdom is humans in!

Propane (C3H8) has a molar mass of 132 g/mole. You started out the day with a tank containing 9071 g of propane. At the end of the day, your tank contained 7532 g of propane gas. How many moles of gas did you use?

Why decomposition of ammonium nitrate is a redox reaction?