Answer:
Lustrous is NOT a property of metal
Answer:
Mercury
Explanation:
Mercury is a liquid element that contains 80 electrons when not charged.
Example:
sample density of gasoline, 20 g of weigth into 5 <span>mL
Answer:
D = m / V
D = 20 g / 5 mL
D = 4 g/mL</span>
Answer
Calculating the mass number for an atom requires that we know the atomic number and the number of protons in the atom’s nucleus. The mass number then gives us the average weight of atoms of a given element. However, as long as the number of protons equals the number of neutrons, the values balance out and we always obtain a whole number for the mass number.
Explanation:
those 3
The amount of Al2O3 in moles= 1.11 moles while in grams = 113.22 grams
<em><u>calculation</u></em>
2 Al + Fe2O3 → 2Fe + Al2O3
step 1: find the moles of Al by use of <u><em>moles= mass/molar mass </em></u>formula
= 60.0/27= 2.22 moles
Step 2: use the mole ratio to determine the moles of Al2O3.
The mole ratio of Al : Al2O3 is 2: 1 therefore the moles of Al2O3= 2.22/2=1.11 moles
Step 3: finds the mass of Al2O3 by us of <u><em>mass= moles x molar mass</em></u><em> </em>formula.
The molar mass of Al2O3 = (2x27) +( 16 x3) = 102 g/mol
mass is therefore= 102 g/mol x 1.11= 113.22 grams
