Question

What is the mass of one atom of copper in grams? A) 65.4 g B) 63.5 g C) 1.06 times 10^-22 g D) 52.0 g E) 58.9 g How many moles of O_2(g) are needed to react completely with 52.0 L of CH_4 (g) at STP to produce CO_2(g) and H_2(g) according to the following balanced equation: CH_4(g) + 2O_2 rightarrow CO_2(g) + 2H_2O(g) A) 4.64 B) 52.0 C) 11.6 D) 2.32 E) none of these Atoms with greatly differing electronegativity values are expected to form A) nonpolar covalent bonds B) polar covalent bonds C) ionic bonds D) no bonds E) triple bonds A compound is analyzed and found to contain 12.1% carbon, 16.2% oxygen, and 71.7% chlorine (by mass). Calculate the empirical formula of this compound. A) COCl_4 B) COC1 C) CO_2Cl D) CO_2C1_2 E) COCl_2 What is the mass of H_2SO_4 in 1.00 times 10^2 mL of 0.200 M H_2SO_4 solution? A) 19.6 g B) 20.0 g C) 1.00 times 10^2 g D) 1.96 g E) none of these

Answer 1

Mass of one Atom of copper in grams: copper molar mass expresses the of imole of copper atoms one mole of any substance contains exactly 6.022 times 10^23 atoms/ molecules of that substance this is known as Avogadro's number . 1 mole of c_u = 6.0221 times 10^23 toms of coppe .c_u molar mass = 63.546 g .6.022 times 10^23 atoms of copper have a mass of 63.456g In order o get the mass of an individual copper atom, divided this mass by how many copper atoms are in 1 mole 1 copper atom 63.456g/6.022 times 10^23 copper atoms = 63.456 g/6.022 times 10^23 = 10.537 times 10^-23g = 1.0537 times 10^-22 g Therefore mass of one atom of copper in grams = 1.05 times 10^-22 g