Answer:
7.71x10^23 molecules
Explanation:
Avogadro's # = 6.022x10^23
1.28 mol SiO2 x 6.022x10^23/ 1 mol SiO2 = 7.71x10^23 molecules
4.1g
Explanation:
Given parameters:
Mass of carbon dioxide = 15g
Mass of oxygen gas = 11g
Unknown:
Mass of carbon consumed = ?
Solution:
Equation of the reaction:
C + O₂ → CO₂
To solve this problem from the balanced equation, we have to use the amount of product formed and work to Carbon. This is because, we are sure of the amount of carbon dioxide formed but the amount of the given oxygen gas used is not precise.
Number of moles of CO₂ = 
Molar mass of CO₂ = 12 + (16 x2) = 44g/mol
Number of moles of CO₂ = 
= 0.34mole
From the equation of the reaction;
1 mole of CO₂ is produced from 1 mole of C
0.34mole of CO₂ will produce 0.34mole of C
Mass of carbon reacting = number of moles x molar mass = 0.34 x 12 = 4.1g
Learn more:
Number of moles brainly.com/question/1841136
#learnwithBrainly
Answer:
A Li2O
Explanation:
Li has a 1+ charge and O has a 2- charge so to balance the charges there needs to be 2 Li for every 1 O
Note that this is occurring at STP, where 22.4L of any gas is equal to 1mol of that gas.
First, convert the liters of O₂ to moles of O₂ using the conversion factor 22.4LO₂ = 1molO₂.
8.6LO₂ × 1molO₂/22.4LO₂
= 8.6/22.4
≈ 0.3839molO₂
Next, convert moles of O₂ to moles of H₂O. In the balanced equation, the coefficients show that there are 2 moles of H₂O for every mole of O₂. So, use the conversion factor 1molO₂ = 2molH₂O.
0.3839molO₂ × 2molH₂O/1molO₂
= 0.3839 × 2
= 0.7678molH₂O
Finally, convert the moles of H₂O to liters of H₂O using the same conversion factor from before, 22.4LH₂O = 1molH₂O.
0.7678molH₂O × 22.4LH₂O/1molH₂O
= 0.7678 × 22.4
≈ 17LH₂O
So, the answer is 17 liters of gaseous water is collected! Note that its rounded to 17 because the measurement given in the problem has 2 sig figs. Hope that helps! :)
Answer:
Beryllium, because it is in period 2 and has four total electrons.
Explanation:
