A sample of an element has a mass of 34.261 grams and a volume of 3.8 cubic centimeters. To which number of significant figures should the calculated density of the sample be expressed?

(1) 5 (3) 3

(2) 2 (4) 4

Give the names of three exothermic and 3 endothermic processes?

For the following reaction, draw the major organic product and select the correct iupac name for the organic reactant. if there is more than one major product, both may be drawn in the same box.

Which of the following best describes valence electrons in a covalent bond

Hypothermic body temperature can range from 28.7 °C to 35.5 °C. What is this range in degrees Fahrenheit?

Which statement I true for photosynthesis? A. Producers use it B. Consumers use it C. Scavengers use it D. Decomposers use it

Which is the balanced chemical equation showing hydrogen peroxide (h2o2) decomposing into hydrogen (h2) and oxygen (o2) ? 1. h2 + o2 → h2o2 2. 2 h2o2 → 2 h2 + o2 3. h2o2 → h2 + o2 4. 2 h2 + o2 → 2 h2o2?

Assuming constant pressure, rank these reactions from most energy released by the system to most energy absorbed by the system, based on the following descriptions: A. Surroundings get colder and the system decreases in volume. B.

Zircon is a mineral with the empirical formula ZrSiO4. If all the zirconium is 90Zr, all the silicon is 28Si, and all the oxygen is 16O, what mass of oxygen is present in 10. g of zircon?

Which property below is not a general property of metals: A. Ductile C. Malleable B. Poor conductor of heat D. High luster

Calculate the number of particles (atoms or molecules) of the following: 1. How many molecules are there in 24 grams of FeF3? 2. How many molecules are there in 450 grams of Na2SO4? 3. How many grams are there in 2.3 x 1024 atoms of silver?