Perid 4 of the periodic table contains the elements potassium, calcium, and copper. Which is least reactive?

3. How many valence electrons are in the outermost energy level of each of the following elements? a. Helium b. Lithium c. Nitrogen d. Magnesium

Three ideal polarizing filters are stacked, with the polarizing axis of the second and third filters at 21 degrees and 61 degrees, respectively, to that of the first. If unpolarized light is incident on the stack, the light has intensity 60.

A spring gains 2.34 joules of elastic potential energy as it is compressed 0.250 meter from its equilibrium position. What is the spring constant of this spring? (1) 9.36 N/m (3) 37.4 N/m (2) 18.7 N/m (4) 74.9 N/m

If gold gets hot enough, it will melt. What type of change is this? A. physical only B. chemical only C. physical and chemical

What will be the acceleration of a 40-kilogram object that is pushed with a net force of 80 newtons?

Which formula is used to calculate the mass of an object if the force and acceleration are known? a: m = Fa b: m = F/a c: m = a/F d: m = F - a

The circulatory system keeps the body and its tissues continuously oxygenated. It does this by having A) veins to carry both oxygenated blood to the tissues and deoxygenated blood to the lungs.

What is the "atomic mass" of an atom?

What type of energy comes from the food that we eat?

Which of the following are vector quantities? check all that apply. a. time b. displacement c. force d. mass