Stoich questions...
1) convert the grams of Au to moles
(33.5g)/(196.7g/mol)=___x___
2)find how many atoms are in that many moles by multiplying it by avogadro's number.
x(moles of Au)*(6.02*10^23)=?
3)now that you have found the number of atoms of gold, convert it to grams of aluminum by multiplying it by Avogadro's number and multiplying it by the atomic mass of aluminum.
( ? )(6.02*10^23)(26.98g/mol)= (mass of Al)
Explanation:
question 44
the number 35 of bromine represents the atomic number
question 45
29 protons,
27 electrons
29-27 = +2
the charge on the following particle is
+2
A is the answer
In an ozone molecule, the three atoms must be connected, so there must at least be a single bond between them. Place
dots in pairs around the oxygen atoms until each oxygen atom has eight valence electrons, starting with the atoms on the
outside and doing the central atom last if there are enough. Do not exceed the total number of valence electrons
identified in part A. Remember that the dashes between the oxygen atoms, which represent single bonds, each indicate
the presence of two valence electrons
Answer:
0.109 g.
Explanation:
Equation of the reaction:
Na3PO4 + 3HCl --> 3NaCl + H3PO4
Number of moles of HCl = molar concentration × volume
= 0.1 × 0.04
= 0.004 mol.
By stoichiometry, 1 mole of Na3PO4 neutralises 3 moles of HCl. Therefore, number of moles of Na3PO4 = 0.004/3
= 0.0013 mol
Mass of Na3PO4 = molar mass × number of moles
= 0.0013 × 164
= 0.219 g
Since 50% of Na3PO4 was present in the sample. Let 100 g be the total mass of the substance
= 0.219 × 50 g/100 g
= 0.109 g.
Answer: Tall fescue can be harmful to grazing cattle and horses because the grass can become tough and infected with endophytes, causing poor grazing. Switchgrass and tall fescue are less likely to be poisonous to dogs, cats or humans than to horses or cattle, but eating either of them might cause stomach upset.
Explanation: