What coefficient has to be placed in front of H2O to correctly balance following equation? Remember that entire equation has to be balanced. B2O3(s) + HF(l) → BF3(g) + H2O(l)

What is the mass in grams of one molecule of propene, C3H6?

Which of the following is the lowest temperature? TK = TC + 273 TF = (1.8 x TC) + 32 TC = (TF – 32) / 1.8

A 2.34 g sample of an element contains 2.71×1022 atoms. What is the element symbol?

Iodine pentafluoride reacts slowly with glass and violently with water. Determine its molecular mass.

Potassium dichromate, K2Cr2O7, is used in tanning leather, decorating porcelain and waterproofing fabrics. Calculate the number of chromium atoms in 78.82 g of K2Cr2O7.

If a car makes 25.0 miles/gal, how many liters of gasoline are needed for a 322 km trip?   (1 mile = 1.609 km, 1 gallon = 3.79 L)

Which one of the following combinations of names and formulas is incorrect?

How many atoms of oxygen are in 126 g sample of carbon dioxide?

Classify each of the following elements as nonmetal, main group metal, transition metal or metalloid.