Choose the letter of the choice that best completes the statement or answers the question.

Which of the elements listed below is a metal with 2 valence electrons?

a.

magnesium

c.

platinum

b.

uranium

d.

chlorine

The leaves of the rhubarb plant contain high concentrations of diprotic oxalic acid (hooccooh) and must be removed before the stems are used to make rhubarb pie. if pka1 = 1.23 and pka2 = 4.19, what is the ph of a 0.0269 m solution of oxalic acid?

i have 5 moles of gas in a container with a volume of 45 liters and at a temperature of 210k, what is the pressure inside the container

A chemist studies two forms of refined gasoline. which of the following branches of chemistry might the chemist us?

A particular nuclide has a mass number of 21 and contains 11 neutrons. What element is it? a. hydrogen b. neon c. sodium d. scandium

As a substance changes phase from a gas to liquid to solid: A - The spacing between molecules increases. B - It's density generally increases. C - The spacing between molecules is not affected. D - It undergoes chemical change.

What happens when the threat of exposure to dirty air is reduced in a community? There is enough oxygen available for people's lungs to function normally The amount of indoor air pollutants released during a fossil fuel burn decreases There is a

Is chicken noodle soup an element, a compound, a homogeneous mixture, or a heterogeneous mixture?

How is the amount of sunlight affect the makeup of an ecosystem

How many moles are in 65 g of carbon dioxide (CO2) ?

kilograms represented by the mass defect for thorium - 234=3.09x 10-27 kg what is the nuclear binding energy for thorium - 234