Hello!
Atomic Number, is the number where the atom lays on the perodic table and can be found through the number of protons. Meaning that gallium has an atomic number of 31 !
Atomic weight, which is equal to 70 in this case, can be found by subtracting the atomic number from that total to find the remaining number of neutrons that make up the mass. So gallium has 31 protons and 39 protons.
Hope this helps answer your question.
Answer:
Percentage mass of copper in the sample = 32%
Explanation:
Equation of the reaction producing Cu(NO₃) is given below:
Cu(s)+ 4HNO₃(aq) ---> Cu(NO₃)(aq) + 2NO₂(g) + 2H₂O(l)
From the equation of reaction, 1 mole of Cu(NO₃) is produced from 1 mole of copper. Therefore, 0.010 moles of Cu(NO₃) will be produced from 0.010 mole of copper.
Molar mass of copper = 64 g/mol
mass of copper = number of moles * molar mass
mass of copper = 0.01 mol * 64 g/mol = 0.64 g
Percentage by mass of copper in the 2.00 g sample = (0.64/2.00) * 100%
Percentage mass of copper in the sample = 32%
5 is the atomic number, 11 is the atomic mass and boron is the element
Answer:
Solvent, substance, ordinarily a liquid, in which other materials dissolve to form a solution.
