Which group of elements are the most important for living organisms?/

a. carbon, lead, and tin

b. carbon, nitrogen, and oxygen

c. boron, aluminum, and nitrogen

d. arsenic, antimony, and oxygen

3.2 moles of CaS to formula units

An iron ore sample contains plus other impurities. A 729-g sample of impure iron ore is heated with excess carbon, producing 277 g of pure iron by the following reaction: What is the mass percent of in the impure iron ore sample?

The frequency of a water wave that has a wavelength of 0.5 m and a speed of 4 m/s

Do females take longer to eliminate alcohol than male, even though they might be the same weight? a. true b. false

How was island hopping a change in strategy for the us military?

Penny bought a club moss plant for her water garden. She needs to know how tall the plant will grow so she knows how much space it will need.

Which of the following is not a producer? Mushroom Tulip Grass Pine Tree

Phosphorus forms a number of oxohalides, x3po, in which x may be a f, cl, or br atom. the most common of these, phosphoryl chloride, is obtained as follows:

Which statement is true about the speed of light waves in a medium? a. Depends on the temperature of the light wave b. Decreases with a decrease in density of medium c. Decreases with an increase in density of medium d.

What's a certain indicator that a molecule is polar? the molecule has a nonpolar covalent bond and the dipole is cancelled due to symmetrical arrangement of atoms the molecule has a polar covalent bond and the dipole is cancelled due to symmetrical