Answer:

Explanation:
Hello,
In this case, we use the Avogadro's number to compute the molecules of C2F4 whose molar mass is 100 g/mol contained in a 485-kg sample as shown below:

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Answer:
See explaination
Explanation:
The invariant mass of an electron is approximately9. 109×10−31 kilograms, or5. 489×10−4 atomic mass units. On the basis of Einstein's principle of mass–energy equivalence, this mass corresponds to a rest energy of 0.511 MeV.
Check attachment for further solution to the exercise.
Answer:
Explanation:
Word equation:
sulfuric acid + ammonium hydroxide → ammonium sulfate + water
Chemical equation:
H₂SO₄ + NH₄OH → (NH₄)₂SO₄ + H₂O
Balanced chemical equation:
H₂SO₄ + 2NH₄OH → (NH₄)₂SO₄ + 2H₂O
The given reaction is the reaction of acid with base. When acid and base react salt and water are produced. In given reaction an acid sulfuric acid and base ammonium hydroxide react and form ammonium sulfate salt and water. The given reaction also follow the law of conservation of mass.
Steps to balance the equation:
Steps 1;
H₂SO₄ + NH₄OH → (NH₄)₂SO₄ + H₂O
H = 7 H = 10
S = 1 S = 1
O = 5 O = 5
N = 1 N = 2
Step 2:
H₂SO₄ + 2NH₄OH → (NH₄)₂SO₄ + H₂O
H = 12 H = 10
S = 1 S = 1
O = 6 O = 5
N = 2 N = 2
Step 3:
H₂SO₄ + 2NH₄OH → (NH₄)₂SO₄ + 2H₂O
H = 12 H = 12
S = 1 S = 1
O = 6 O = 6
N = 2 N = 2
Answer:
4.427 × 10⁵
Explanation:
In mathematics, rounding up a number is a way to get a more simpler figure but not too distant from the original number. Rounding up a whole number like this (442722) to significant figures means having only four non-zero digits in the figure i.e. 442722 ~ 442700.
This means that 442722 has been rounded up to 4s.f. Hence, to use scientific notations to represent our answer, we count the number of decimal places from right to left i.e.
442700 = 5 decimal places if the point is between 4 and 4 i.e. 4.427
Therefore, the figure 442700 can be written as 4.427 × 10⁵ using scientific notation.