Which of these is a heterogeneous mixture?

a. air

b. soil

c. steel

d. salt water

The activation energy for a given reaction is 56 kj/mol. at what temperature would the rate constant be quadruple what is was at 273k?

Which is an advantage of using chemical indicators?

What phylum would a flowering plant that produces seeds belong?

1. explain how you would make 100 mL of a 2.0% (w/v) solution of sodium chloride? 2. How many grams of magnesium sulfate are required to make 250 mL of a 1.6% MgSO4 (m/v) solution? 3. A solution contains 2.7 g of CuSO4 in 75 mL of solution.

A candle is 10 cm high and 2 cm in diameter physical or chemical property

How many moles of oxygen are needed to make 6.50 moles of magnesium oxide?

Which of the following happens during a chemical change? Check all of the boxes that apply. One atom or more changes into atoms of another element. New substances with different properties are formed. Solids, liquids, or gases may form.

What material was added to powdered rock during tuttle and bowen's experiments?

Which of the following statements is true? Selected Answer: D. At least two of the above statements (A-C) are true. Answers: A. Ions are formed by adding or removing protons or electrons. B. Scientists believe that solids are mostly open space. C.

Does anybody know which element from the periodic table that has 19 electrons and 24 neutrons, for atomic charge.