Which of the following is a true statement?

Chemical changes are not ever useful.

A chemical change changes only the size of the matter.

A chemical change makes different matter from old matter.

An ice cube melting is a chemical change.

In the space provided below, draw electron-dot diagrams for the following molecules: hydrogen (H2), ammonia (NH3), and methane (CH4). Remember that the dots represent the valence electrons.

What is an example of a physical change in weight

What animal undergoes incomplete metamorphosis

Carbon has an atomic number of 6. How many electrons are in a carbon atom's second energy level?

Light waves come in different wavelengths and frequencies. The color of the light we see is dependent on wavelength. When we see a rainbow, we are actually seeing

Describe how you could determine the specific heat of a sample of a solid substance. You may assume that the substance does not react with water.

Combustion of 7.54 g of liquid benzene (C6H6) causes a temperature rise of 50.3°C in a constant-pressure calorimeter that has a heat capacity of 6.27 kJ/°C. What is ∆H for the following reaction? C6H6 (l) + O2 (g) → 6CO2 (g) + 3H2O (l)

What is the compound name for the ion chemical formula AgBr?

Which principal energy level of an atom contains an electron with the lowest energy? A) n=1 B) n=2 C) n=3 D) n=4

Are erasers made from rubber?