Chemistry exam 1

Which of the following is not a pure substance? a. oxygen gas b. nitrogen gas c. air d. argon gas e. table salt

c

What is the symbol of the ion having 17 protons and 18 electrons?

Cl^-

Cesium is an example of ______

an alkali metal

55/25Mn^2+ ion has _____ protons, ______ neutrons, _____ electrons a. 30;25;30 b. 25;30;23 c. 30;25;23 d. 23;30;25 e. 25;30;25

b

Which of the following is an alkaline earth metal? a. Na b. Mg c. Cu d. Al e. K

b

which temperature is below 300 K? a. 28C b. 75F c. 30C d. all e. 85C

b

who discovered electrons? a. robert boyle b. robert millikan c. albert einstein d. John dalton e. JJ Thompson

e