Please be specific. Which umbrella?
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
same number of protons and different number of neutrons are called isotopes
Answer is C. 2, 3 and 5 shows how as the number of carbon increase, butane, pentane and hexane (4,5 and 6 carbons) the octane number does decrease
Answer:
V = 20.97 L
Explanation:
Given data:
Mass of nitrogen = 23.4 g
Pressure of gas = 750 mmHg (750/760 = 0.99 atm)
Temperature of gas = 28°C (28+273= 301K)
Volume of gas = ?
Solution:
First of all we will calculate the number of moles of gas.
Number of moles = mass / molar mass
Number of moles = 23.4 g/ 28 g/mol
Number of moles = 0.84 mol
Now we will calculate the volume:
PV = nRT
V = nRT/P
R = general gas constant = 0.0821 atm.L/mol.K
V = 0.84 mol× 0.0821 atm.L/mol.K× 301 K / 0.99 atm
V = 20.76 L/0.99
V = 20.97 L
