Answer:
76
Explanation:
128 is the mass number. it means protons+nutrons=128
then the atomic number of te-128 is 52. atomic number means the number of protons .
so 128-52=76.
if you don't get it, I'll explain it later
Solution :
In the process to isolate gold that has a 80 percent yield, a 3.00 g of Au is being isolated.
That is, the actual yield of Au is 3. 00 g
Therefore, we need to find the theoretical yield.
As we know,
As actual yield = 3.00 g
percent yield = 80 %
So, theoretical yield = 
= 3.75 g
Thus he should be able to get 3.75 g which is the theoretical yield of Au.
Answer:
0.702M
Explanation:
Molarity of a solution, which refers to the molar concentration of that solution can be calculated thus;
Molarity = number of moles (n) ÷ volume (V)
Firstly, we convert 18.5 grams of NaCl to moles using the formula; mole = mass/molar mass
molar mass of NaCl = 23 + 35.5 = 58.5g/mol
mole = 18.5/58.5
mole = 0.32moles
Volume of water (V) = 450mL = 450/1000 = 0.450L
Molarity = n/V
Molarity = 0.32/0.450
Molarity = 0.702M
To answer this, we use Raoult's Law where the partial pressure is equal to the product of the fraction of the gas in the mixture and its total pressure. Also, we use Dalton's Law of Partial Pressure where the total pressure is equal to the sum of the partial pressure of the gases in the mixture.
Ptotal = 73.44 + 128.52 + 2.04 = 204 atm
201.96 = x (204)
x = 0.99
120 barrels = 15120 quarts
To convert from barrels to quarts, you just need to multiply the value in barrels by 126 (the conversion factor).
So, 120 barrels = 120 × 126 = 15120 quarts.
