Which type of substance is made of only one kind of matter and has definite properties?

Which produce would best increase the amount of heat energy that is actually gained by calorimeter b

If a simple machine aduces the strength of a force, what must be increased? the speed of the input force the work the simple machine performs the size of the simple machine the distance over which the force is applied

The concentration of ionic substances is important for the heart to beat. your heart responds to electrical impulses that travel through heart cells that are made up mostly of water. which properties of ionic compounds are important to support this function? solubility in water conductivity crystalline melting point