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Please help me to answer all of them. I don't have any morequestions and no money to buy more, and this is my lastquestion.
1.a.
1.b.
(a) Atoms are very small compared to objects on the macroscopic scale. The radius of a copper atom is 128 pm. What is this value in meters and in centimeters? m (b) The mass of a single copper atom is 1.06x10-22 g. Suppose enough Cu atoms were lined up like beads on a string to span a distance of 46.1 cm ( 18 inches). How many atoms would be required? atoms What mass in grams of Cu would be used? Could you weigh out this amount of copper using a typical laboratory balance? (c) Taking the density of copper metal to be 8.98 g/cm3, calculate the mass of metal needed to form a piece of Cu wire with the same length as the distance in b, but with a diameter of 1.00 mm. Hint: The volume of a cylinder is n times its radius squared times its height. (V = n r² h) g How many copper atoms does this represent? g cm atoms
The molecular liquid dichloromethane (CH₂Cl2) has a density of 1.33 g/mL, while the molecular liquid dibromomethane (CH₂Br₂) has a density of 2.48 g/mL. (a) When 66.8 mL of CH₂Cl2 and 23.4 mL of CH₂Br2 are mixed, a clear liquid solution forms. Is this a chemical or a physical change? Is the solution a pure substance, a homogeneous mixture or a heterogeneous mixture? (b) Is the density of this solution a chemical or a physical property? (c) Assuming that the volumes are additive upon mixing, what is the density of the solution? g/mL