Which chemical equation is unbalanced?

1. C + O2 → CO2

2. Sr + O2 → 2SrO

3.6H2 + 3O2 → 6H2O

4. H2 + H2 + O2 → H2O + H2O

The correct symbol for the ion formed by nitrogen is:

Scientific explanations of natural phenomena are based on A. opinion polls of scientists. B. only the observations made by a single scientist. C. only the most recent empirical evidence. D. all the empirical evidence available.

What is the temperature of 0.52 mol of gas at a pressure 131.722kpa and a volume of 11.8l

1) These are barrel shaped microtubules in most animal cells, that organize the spindles during cell division

Which statement best describes the movement of atoms in a solid? They are able to slide past each other. They spread apart as far as possible. They have no freedom to move. They are free to move in all directions.

18. which bond is most polar? H--F H--Cl H--Br H--I

What kind of reaction is ca (s) + h3po4 (aq) ca3 (po4) 2 (s) + h2 (g)

In the teapot dome scandal, what did the secretary of the interior albert fall lease

A Material made of equal parts is called what? A. Atom, B. Pure substance, C. Mixture

Part C Why are dichotomous keys useful in classifying a new species?