In any chemical compound the elements are always combined in the same proportion by__.

a) charge

b) mass

c) volume

d) density

Which answer choices correctly describe properties of covalent compounds? Select all that apply.

What is the maximum number of grams of PH3 that can be formed when 6.2 g of phosphorus reacts with 4.0 g of hydrogen to form PH3?

Which is a conversion factor for this statement of equality: 12 in. = 1 foot? 12 feet1 in. 12 feet 1 in. 1 in. 12 feet 1 in. 12 feet 1 foot12 in. 1 foot 12 in. 1 foot1 in. 1 foot 1 in.

What does the half-life of a radioisotope correspond to?

The volume of a given container is 6.2 L, with 19.2 moles of a gas. How many miles are there if we increase the volume to 10.0L

What did scientists observe using the earliest microscopes

Which statement describes the redox reaction that occurs when an object is electroplated? A. It is spontaneous and requires an electric current. B. It is spontaneous and produces an electric current. C.

How are electromagnetic different than all other waves

Find the ratio of speeds of an electron and a negative hydrogen ion (one having an extra electron) accelerated through the same voltage, assuming non-relativistic final speeds. Take the mass of the hydrogen ion to be 1.67*10^{-27} kg.

A type of rock that undergoes changes because of heat and pressure