Answer:
The answer to your question is 27 g of Al
Explanation:
Data
mass of Al = ?
moles of Al₂O₃ = 0.5
The correct formula for the product is Al₂O₃
Balanced chemical reaction
4Al + 3O₂ ⇒ 2Al₂O₃
Process
1.- Calculate the molar mass of the product
Al₂O₃ = (27 x 2) + (16 x 3)
= 54 + 48
= 102 g
2.- Convert the moles of Al₂O₃ to grams
102 g ---------------- 1 mol
x ---------------- 0.5 moles
x = (0.5 x 102) / 1
x = 51 g of Al₂O₃
3.- Use proportions to calculate the mass of Al
4(27) g of Al --------------- 2(102) g of Al₂O₃
x --------------- 51 g
x = (51 x 4(27)) / 2(102)
x = 5508 / 204
x = 27 g of Al
Mg + O2 ➡️ MgO — we need to have the same emount of each element on both sides. On the left we have 1 Mg and on the right 1 Mg, so thats fine, but 2 O on the left and 1 O on the right, so we place a coefficient of 2 in front of the compound which is “lacking” O.
Mg + O2 ➡️ 2MgO
Now the O is okay, but we have 1 Mg and 2 Mg, so we need to put a 2 in front of the Mg thats “lacking”.
2M + O2 ➡️ 2MgO
Now it is balanced :)
Noble gases hardly ever participate in chemical reactions because they already have 8 valence electrons and are the most stable among other elements.
Therefore, C. noble gases is the correct answer.
Hope this would help~
Metals are placed in one spot,the nonmetals are placed in another spot,And lastly the metalloids are seperated
The concentration of the solution is also known as Molarity (M). The formula for molarity is
M = mol / liters
We already have the liters, so we only need to find moles. We can find the number of moles by using the molar mass of NaCl and the given amount. That can be found using the elements' atomic weights given on the periodic table.
22.990 (mass of Na) + 35.453 (mass of Chlorine) = 58.443 g / mol
That's how many grams are in one mole of NaCl, but we only have 2.5 grams. So, let's divide and see how many moles we have.
2.5 / 58.443 = .042776 moles
Now we can plug our numbers into the formula.
M = .02138 mols/L
So, your concentration is about .02 mol/L.