Which statement describes evidence of a chemical reaction?

a. ice melting

b. water boiling

c. lighting a match

d. grape juice freezing

10 Salt water is classified as a (1) compound because the proportion or its atoms is fixed (2) compound because the proportion of its atoms can vary (3) mixture because the proportion of its components is fixed (4) mixture because the proportion of

Electric power plants are the main source of: carbon monoxide nitrogen oxides hydrocarbons particle pollutio

You are asked to analyze an aqueous solution (X) and determine what's in it. You pour some of your sample X into a test tube and add a few drops of an acid. No observable reaction occurs.

How might the simulation look different if the mercury (ii) bromide was created from two salts, such as mercury (ii (nitrate and sodium bromide, rather than added directly?

The mass and charge of all three sub atomic particles

Why do the chemical properties cycle through each period? Every eighth element starting with hydrogen restarts the transition from metal to inert gas. Elements with atomic numbers which are multiples of eight start a new period.

Which statement correctly describes the Ka of a weak acid? The Ka is large, and the equilibrium favors products. The Ka is large, and the equilibrium favors reactants. The Ka is small, and the equilibrium favors products.

True or False? The fatal 1930 incident in Muese Valley, Belgium, was associated with leakage of toxic chemicals from a former dump site.

How many moles of neon (Ne, 20.179 g/mol) are in 68.4 grams of neon

A 50.00 mL sample of groundwater is titrated with 0.0300 M EDTA. Of 12.40 mL of EDTA is required to titrate the 50.00 mL sample, what is the hardness of the groundwater in molarity and in parts per million of CaCO 3 by mass