The chemical symbol for a calcium ion is ca2. what does the 2 symbolize

A hypothesis wich appears to be verified by multiple experiments and or researchers may become a

Why is density considered a physical property rather than a chemical property of matter?

Why do many gas-phase reactions occur with rapid kinetics, whereas solid-phase reactions occur slowly? a. In gas phase reactions, the reactants are more abundant and so the reaction is faster. b.

A 7.5 L cylinder contains 5 moles of gas at a temperature of 274°C. What is its pressure in kiloPascals (kPa) ?

The compound methyl butanoate smells like apples. Its percent composition is 58.8% C, 9.8% H, and 31.4% O, and its molar mass is 102 g/mol. Calculate the empirical and molecular formulas for this compound.

Ionic compounds are formed by the ... of electrons? by the what?

What is it called when energy is created without oxygen?

If 21.3 grams of lithium react with excess water, how many liters of hydrogen gas can be produced at 297 Kelvin and 1.40 atmospheres? Show all of the work used to solve this problem. 2Li (s) + 2H2O (l) - > 2LiOH (aq) + H2 (g)

How did coroners handle their responsibilities in the early 1900s? Why was there a need for significant change in the job?

Which of the following is the best indication that a chemical change has taken place? a. The matter changes color. b. A mixture separates into layers. c. The change is reversible. d. The shape of the substance changes.