Which of the following is an example of an irreversible physical change? a. boiling soup b. burning wood c. freezing water d. cracking an egg

When atomic orbitals of two nuclei overlap, the mutual attraction between a negatively charged electron pair and the two positively charged nuclei forms: (A) a covalent bond (B) an ionic bond (C) an orbital bond (D) none of the above

When 6.00 g of sulfur are combined with 6.00 g of oxygen, 12.00 g of sulfur dioxide (so2) are formed. what mass of oxygen would be required to convert 7.00 g of sulfur into sulfur trioxide (so3) ?

What causes clouds to form on the upwind side of mountain ranges

Two molecules of one reactant combine with 3 molecules of another to produce 5 molecules of a product. Which equation is the correct representation of the reaction? 2A+3B→5C A2+B3→C5 2A+5B→3C A2+B3→C3

For which compound is the process of dissolving in water exothermic? (1) NaCl (3) NH4Cl (2) NaOH (4) NH4NO3

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