Answer:
See explanation
Explanation:
Given Einstein's theory of relativity, we have that;
E= mc^2
m= mass of the substance
c= speed of light
For one gram of the substance,
E= 1 ×10^-3 × (3 × 10^8)^2
E = 9 × 10^13 J
For 8.7 g of matter;
E = 8.7 × 10^-3× (3 × 10^8)
E= 7.83 ×10^ 14 J
Answer:
A. 0.0440 moles/day
Explanation:
First, let's figure out how many moles 33.23 grams of silver is. We do this by dividing the number of grams by the molar mass of silver, which is 107.87 g/mol:
33.23 g Ag ÷ 107.87 g/mol = 0.3081 mol Ag
Now, let's divide this by 7 to get the rate per day:
0.3081 mol Ag ÷ 7 days = 0.0440 mol/day
Thus, the answer is A.
Answer:
The empirical formula is ZnO2
Explanation:
What is the empirical formula for a compound which contains 67.1% zinc and the rest is oxygen?
Step 1: Data given
Suppose the compound has a mass of 100.0 grams
A compound contains:
67.1 % Zinc = 67.1 grams
100 - 67.1 = 32.9 % oxygen = 32.9 grams
Molar mass of Zinc = 65.38 g/mol
Molar mass of O = 16 g/mol
Step 2: Calculate moles of Zinc
Suppose the compound is 100 grams
Moles Zn = 67. 10 grams / 65.38 g/mol
Moles Zn = 1.026 moles
Step 3: Calculate moles of O
Moles O = 32.90 grams / 16.00 g/mol
Moles O = 2.056 moles
Step 4: Calculate mol ratio
We divide by the smallest amount of moles
Zn: 1.026/1.026 = 1
O: 2.056/1.026 = 2
The empirical formula is ZnO2
To control this we can calculate the % Zinc for 1 mol
65.38 / (65.38+2*16) = 0.67.1 = 67.2 %
Answer:
A: 20 km/h, B: 10 km/h
Explanation:
Speed of Vehicle A = 40-20/ 2-1
=20 km/h
If A is 20km/h, B is 10km/h as given in option
