Which of these is an example of physical change?

1) water evaporates

2) gasoline ignites

3) a nail rusts

4) wood rots

What information is given in a chemical formula?

What pressure is exerted by a mixture of 2.80 g of H2 and 6.100 g of N2 at 273°C in a 10.0 L container?

Elle is pushing a box of mass 7.0 kilograms with the force of 25 newtons. If the force of friction is 2.6 newtons, what is the value of acceleration of the box?

What is the chemical makeup of a rock?

If an alkane contains five carbon atoms, how many hydrogen atoms will it contain?

A material that cannot be broken down farther by chemical means

How many of the following elements have 2 unpaired electrons in the ground state? C Te Hf Si A) 1. B) 2. C) 3. D) 4.

Which has a higher frequency, a neutron or electron? Why?

1) Identify the intensive properties of a sample of matter: A. mass B. hardness C. color D. volume E. reflectivity

Suppose you have a buffer containing 0.400 M hydrazine and 0.300 M hydrazinium chloride at equilibrium. Then you add 25.2 g of NaOH to 2.0 L of the buffer. What change in pH is caused by the addition of the base? A) 0.99 B) 0.40 C) 8.71 D) - 0.36