Describe in three sentences how Ca (Calcium) can get a positive two charge?

What role does weathering have in shaping earth’s surface? a) it allows sediments to fall out of a medium. b) it sediments settle on a new surface. c) it breaks down older material into sediments. d) it transports sediments to a different location. will give brainliest, answer quickly.

What is the volume of 2.5 moles of nitrogen gas (n2)at standard temperature and pressure (stp)?

1) a light bulb takes in 30 of energy per second. it transfers 3j as use energy. calculate the efficiency. second. it transfers 3j as useful light energy and 27j as heat energy. calculate the efficiency