What are two reasons that the noble gases had escaped notice?

The empirical formula of styrene is ch; the molar mass of styrene is 104.14 g/mol. how many h atoms are present in a 2.20 g sample of styrene?

How many calories are there in a 255 Food Calorie snack bar? a. 1 x 103 b. 2.55 x 105 c. 1.07 x 103 d. 60.9 e. none of the above

Which element is the most reactive out of the list below? A. nickel B. iron C. helium D. chlorine

MgCO3+HCl->MgCl2+H2CO3

Which of the following best explains why most chemical reactions proceed more quickly when the concentrations of reactants are increased? a. The increased concentration increases the number of collisions between molecules. b.

What conclusion can be drawn from the statement that an element has low electron affinity, low electronegativity, and a low ionization energy?

A scientist performs an experiment in which a radium-226 (Ra-226) atom decays into radon-222 (Rn-222). The scientist concludes that some energy must have been added to the system to cause this reaction to begin.

Which suitable method can be used to separate a mixture of sand and paraffin

How many vowels does the word love have

What is silicon used for? -matches -gunpowder -glass -steel can coating