explain why some metals are found to occur freely in nature while other occur only as compound with example of each types of metals

Which of the following statements is incorrect? A - 0.25 mole of C has the same number of atoms as 0.25 mole of Hg. B - 1 mole of hydrogen atoms equals 1 mole of helium atoms. C - 1 mole of carbon atoms and 1 mole of oxygen atoms are a 1:1 ratio.

A chemistry student needs 65.0g of acetone for an experiment. She has available 250. g of a 12.5% w/w solution of acetone in chloroform. Calculate the mass of solution the student should use.

A change in the number of protons or neutrons occurs in which type of reaction? A: electrochemical reaction B: thermochemical reaction C: nuclear reaction D: chemical reaction

If your lab procedure instructs you to add two parts of acid to each one part of water and you start with 25 ml of water, how much acid will you add, and how will you add it

What acid and base form Ca3 (PO4) 2

In which orbital does an electron in a bromine atom experience the smallest?

What characteristics of water allow it to have high surface tension?

Obtaining scientific data from a distance is called?

What is organic chemistry?

What is the total number of electrons shared in a double covalent bond between two atoms? (1) 1 (3) 8 (2) 2 (4) 4