Why is evaporation of water a physical change? In terms of substances, why is evaporation of water a physical change and not a chemical change?

A reaction involves the parts of two compounds switching places to form two new compounds. What type of reaction is this? A) synthesis B) decomposition C) single displacement D) double displacement

How many atoms are in 5 moles of phosphorous (P) ?

A sample of an unknown substance is decomposed and is found to be 59% strontium (Sr), 8.0% carbon, and 33% oxygen. What is its empirical formula?

When an atom loses electrons it becomes?

Which is an inner planet? Neptune earth Saturn Jupiter

Which of the following is not true about the importance of the carbon cycle to living things? a. Plants use carbon dioxide to make energy. b. Carbon is the second most abundant molecule in organisms. c.

Fruit flies can either have a brown body or a black body. The allele for a brown body (B) is dominant to the allele for a black body (b). A brown fruit fly was crossed with a black fruit fly as shown below.

A light-year measures the distance a light beam can travel in one year. One light-year is equal to 9 500 000 000 000 kilometers.

The first ionization energy, e, of a potassium atom is 0.696 aj. what is the wavelength of light, in nm, that is just sufficient to ionize a potassium atom? values for constants can be found here.

A gene is a to a chromosome as (A) a pea is to a pod (B) a front to a back (C) a bike is to a car (D) a building is to a window