Classify each of the following as a compound, ahomogeneous mixture, or a heterogeneous mixture: (a) orangejuice; (b) vegetable soup; (c) cement; (d) calcium sulfate; (e) tea

A standard curve for absorbance vs. concentration has an equation of y = 2.0x.  If an unknown compound has an absorbance of 0.856, what is its concentration? Units not required. Report your answer to the correct number of significant figures.

During an exam a student broke into a sweat and 4.23x1022 water molecules erupted on their forehead. How many drops of water is this? Assume one drop of water is 50.0 microliters and the density of water is 0.997g/mL? Use these atomic masses: H = 1.008 amu; O = 15.999 amu Not these answers:  0.07 25 25.38

What did Lavoisier Vine about the mass of the container with reactants and the mass of the container with products and his experiment with Mercury II oxide.

The amounts of gold (Au) in the three gold bullion coins are shown below. Indicate which of the coins contains the smallest and largest amount of gold. Centenario (Mexico), 37.5 g Au Krugerrand (South Africa), 0.158 mol Au Gold Panda (China), 9.17 x 1022 atoms Au

2 NazPO4 ( ) + _CaCl2 ( ) NacI ( )+ Ca3(PO4)2 ( ) The spectator ions in this equation (after balancing and filling in the states of matter) are (Be sure to include coefficients & chemical symbols, as well as the charges of the ions. No need to worry about making the charges subscript or typing ^ for these.) and

Calculate the mass of tetraborane (B4H₁0) that contains a million (1.00 x 10°) boron atoms. Be sure your answer has a unit symbol if necessary, and round it to 3 significant digits. x10 X 5 ?

How many grams of oxygen (O) are present in a 6.41 g sample of potassium nitrate (KNO3)? Enter your answer in decimal form with the correct number of sig figs. Use the proper abbreviation for the units. NOTE:  If you have taken chemistry before and know what diatomic means, do not take that into consideration.  Use just O for this.  There are reasons for this.

A piece of alminum foil contains 3.6 x 1021 aluminum atoms.  1) What is the mass of the aluminum foil in grams? 2) The density of aluminum is 2.7 g/cm3. What is the volume of the foil in cm3? 3) Rolls of aluminum foil are 310 mm wide and 0.016 mm thick (height). What length of foil in centimeters contains 3.6 x 1021 aluminum atoms?

Which of the following is not true?