Which is an element

A. H2O

B NaCl

C Mg

D CO

Why did native americans fear the encroachment of settlers?

Nickel has 28 protons if it has 31 neutrons, what is it's atomic mass? A) 3 B) 28 C) 31 D) 59

Calculate the rate of heat required to bring 7.20 mol/hr of HBr gas from 43.0 degree C to 225.0 degree C at atmospheric pressure.

Antibiotics are often effective treatments for diseases caused by bacteria. viruses. some bacteria and some viruses. all bacteria and all viruses.

What type of reaction takes place when the melting of a solid occurs?

During a nuclear reaction, mass is converted into (1) charge (2) energy (3) isomers (4) volume

The temperature reading of - 14°C corresponds to a Kelvin reading of: -287 K. 287 K. 297.6 K 259 K.

If element X consists of 64.6% of atoms with a mass of 34.0 u, 18.2% of atoms with a mass of 35.0 u, and 17.2% of atoms with a mass of 36.0 u, what is the average atomic mass of element X to the nearest hundredth?

Water has a K, value of 1x 10-13 1x 10-10 1x 10-15 1x 10-14

What evidence do scientists use to explain how the solar system formed? A) All the planets were a result of solar flares from the sun. B) All the planets are made of the same material, mainly helium.