Im pretty sure it would also be 25
Assuming the person has about 154 pounds (70kg) the weight of an average human. There would be around 7000000000000000000000000000 atoms
or 7 x 10^27
Answer:
13. 2g
14. 5000mL
15. 104,000m
16. 160mm
17. 5600000mg
18. 10hs
19. 0.250km
20. 1daL
Explanation:
13. 1000milligram (mg) = 1gram (g)
Hence, 2000mg = 2000/1000
= 2g
14. 1 litre (L) = 1000millilitre (mL)
Hence, 5L = 5 × 1000
= 5000mL.
15. 1kilometre (km) = 1000metre (m)
Hence, 104km = 104 × 1000
= 104,000m
16. 1 centimetre (cm) = 10millimeters (mm)
Hence, 16cm = 16 × 10
= 160mm
17. 1kilogram (kg) = 1000000 milligram (mg)
Hence, 5.6kg = 5.6 × 1000000
= 5600000mg
18. 1 second (s) = 0.01 hectosecond (hs)
Hence, 1000s = 1000 × 0.01
= 10hs
19. 1000metre (m) = 1kilometre (km)
Hence, 250m = 250/1000
= 0.250km
20. 1 centiliter (cl) = 0.001 Decaliter (daL)
Hence, 1000cl = 1000 × 0.001
= 1daL
Answer:
1.70
Explanation:
The molar mass of perchloric acid is 100.46 g/mol. The moles corresponding to 484 mg (0.484 g) are:
0.484 g × (1 mol/100.46 g) = 4.82 × 10⁻³ mol
4.82 × 10⁻³ moles are dissolved in 240 mL (0.240 L) of solution. The molar concentration of perchloric acid is:
4.82 × 10⁻³ mol/0.240 L = 0.0201 M
Perchloric acid is a strong monoprotic acid, that is, it dissociates completely, so [H⁺] = 0.0201 M.
The pH is:
pH = -log [H⁺] = -log 0.0201 = 1.70
