Alculate the heat change in calories for freezing 40 g of water at 0 ∘C . Express your answer as a positive value using two significant figures and include the appropriate units.

2.0 cal

3200 cal

0.50 cal

40.0 ca

Which statement is best described as a atom

What is a possible quantum number set for an electron in the 3s orbital of a magnesium atom

Which of these statements best explains why space exploration should be encouraged? it prepares humans to live without oxygen. it dispel myths about objects in space. it prevents comets and asteroids from striking earth. it creates technology to absorb harmful radiations in space.