A copper atom has a mass of 1.06 × 10 -22 g and a penny has a mass of 2.5 g. Use this information to answer the questions below. Be sure your answers have the correct number of significant digit What is the mass of 1 mole of copper atoms? Round your answer to 3 significant digits. How many moles of copper atoms have a mass equal to the mass of a penny? Round your answer to 2 significant digits.

Please answer question number 2  correctly with the correct answer. there is a picture of an example of a ''Dimensional analysis Format' below. please write out all work showing the math in dimensional analysis format. (please show all work)   Question 8: Calculate the mass in grams of each of the following:   C.) 0.00100 mol silicon tetrahydride (SiH4)   D. ) 1.50 x 10^-2 mol molecular oxygen (O2)   E. 2.30 mol ethylene glycol (C2H6O2)

A 81.15 g sample of a compound containing potassium, chromium and oxygen is analyzed as containing 21.57 g potassium and 28.69 g of chromium.. What mass of oxygen is contained in 287.1 g of this compound? Express your answer in decimal notation rounded to the correct number of significant figures.

Mass of one a mu)Carbon Type 1                                12.0Carbon Type 2                                 13.0 What is the average mass of carbon in this sample? Is this number on the periodic table?( it may be rounded off ) where?