Which sample is a pure substance?

A. a test tube of zinc oxide

B. a container of zinc and oxygen

C. a flask of pond water

D. a jar of soil

Explain why the energy harnessed per person (per capita) has increased so dramatically since the industrial revolution.

What is the mass, in grams, of a pure gold cube that has a volume of 3.20 cm3?

Three structural isomers have the formula c5h12. Draw the three different isomers according to the number of c atoms in their main chain.

How many valence electrons are in an atom with the electron configuration in example A? Example A: 1s22s22p63s23p64s1 7 1 6 19

The formula H2SO4 is representative of which of the following? A. an acid B. a catalyst C. an organic compound D. a base

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