What is a physical combination of substances? A. a compound B. a molecule C. a mixture D. an element

The following reaction shows sodium carbonate reacting with calcium hydroxide. Na2CO3 + Ca (OH) 2 → NaOH + CaCO3 How many grams of NaOH are produced from 20.0 grams of Na2CO3? (Molar mass of Na = 22.989 g/mol, C = 12.01 g/mol, O = 15.

Calculate the radius of an iridium atom, given that ir has an fcc crystal structure, a density of 22.4 g/cm3, and an atomic weight of 192.2 g/mol.

The pH of a solution is 7.880. What is the concentration of [H30+] in the solution?

What is the concentration of NO3 - ions in a solution prepared by dissolving 30 g of Ca (NO3) 2 in enough water to produce 300. mL of solution. a. 0.305 M b. 0.609 M c. 0.806 M d. None of these

What is the markownikoff rule?

A precipitate of zinc hydroxide can be formed using the reaction below. ZnCl2 (aq) + 2 KOH (aq) → Zn (OH) 2 (s) + 2 KCl (aq) If excess KOH is used, the zinc hydroxide will form zincate ions and dissolve in the solution according to the chemical

Which of the following is the correct (unbalanced) equation for the reaction that takes place when solid phosphorus combines with oxygen gas to form diphosphorus pentoxide? A. P (s) + O2 (g) - -> P2O5 (s) B. P2O5 (s) - -> P2 (s) + O2 (g) C.

Nonrenewable resources are natural resources that are limited in supply and cannot be replaced as quickly as they are used up. True or false

Which method for treating arthritis is an example of pseudoscience? diet drugs exercise magnets

Only a small portion of the organisms that lived in the geologic past have been preserved as fossils. Which condition best increases the chance that an organism will become fossilized?