What are the element represented by [He]2s2

Chalcopytite is the ore for which mineral A. iron B. gold C. copper D. aluminum

Gamma rays are produced by applying

Unit conversions. (a) Convert 10,000 dynes to units of lbm ∙ ft/s^2 and lbf (b) Convert 0.2 atm to units of Kpa and lbf/in^2 (c) Convert 37 °C (physiological temperature) to units of °F and K. (d) Convert 50 in 2 ∙ lbm/s^2 units of joules and cal.

This is our main source of heat

How many atoms of gallium are in 2.85x103 g of gallium?

What are the building blocks

If the specific heat of copper is 0.711 J/g•°C, how much copper would it take if the heat given off is 54.85 calories and the temperature change is 205°C.

Why is it is difficult to compress a liquid? a. liquid takes the shape of its container. b. the liquid particles flow away when compressed. c. liquid becomes solid when compressed. d. the liquid particles are very close together.

A mixture of two compounds, a and b, was separated by extraction. after the compounds were dried, their masses were found to be: 105 mg of compound a and 91 mg of compound b. both compounds were recrystallized and weighed again.

What are the five types of chemical reactions?