In a sample of sulfur weighing 4.07 g, how many moles of sulfur are present
and what is the total number of sulfur atoms in the sample?
Determine the name of the mystery element if a 2.80 x 10^22 atom
sample of the element has a mass of 4.24g.
How many K atoms are present in 225mL of milk containing 1.65mg K/mL?
How many K (potassium) atoms are present in 1.2 L of milk containing 2 mg
K/mL? (molar mass of K = 39.10 g/mol)
How many molecules are in a 1µg sample of isopentyl acetate (C7H14O2)?
How many atoms of carbon are present in this sample?
A certain compound called B has x number of magnesium atoms per
molecule of B. The oxidation of 200 g of B produced 500 mg of MgO. How many
magnesium atoms are present in one molecule of B? Assume that the initial amount of
magnesium present in B reacted to produce MgO and the molar mass of B is 32260
g/mol. (molar mass of MgO = 40.3044 g/mol)
The haemoglobin content of blood is about 15.5g/100mL blood. The molar
mass of the haemoglobin is 64500g/mol. There are about 4 iron atoms in a
haemoglobin molecule. How many atoms of Fe are in 6.0L of blood?
Indicate which of the following quantities contains the greatest number of
6.022 x 10
25.0 g nitrogen
52.0 g Cr
Fe (density = 7.86 g/cm
An alloy that melts at about the boiling point of water has Bi, Pb, and Sn
atoms in the ratio of 10:6:5, respectively. What mass of alloy contains a total of one
mole of atoms?
What is the mass composition (in %) of halothane, C
(Molar mass: C = 12 g/mol, H = 1.01 g/mol, Br = 79.90 g/mol, Cl = 35.45 g/mol, F =