We can use the ideal gas law equation for the above reaction to find the number of moles present
PV = nRT
P - pressure - 1.41 atm x 101325 Pa/atm = 142 868 Pa
V - 109 x 10⁻⁶ m³
R - 8.314 Jmol⁻¹K⁻¹
T - 398 K
substituting the values in the equation
142 868 Pa x 109 x 10⁻⁶ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 398 K
n = 4.70 x 10⁻³ mol
number of moles = mass present / molar mass
molar mass = mass / number of moles
= 0.334 g/ 4.70 x 10⁻³ mol = 71.06 g/mol
halogens exist as diatomic molecules
Therefore atomic mass - 71.06 / 2 = 35.5
halogen with 35.5 g/mol is Cl
unknown halogen is Cl
Answer:
1 M
Explanation:
The molarity of a solution, M, is a measure of the concentration of that solution and it refers to the number of moles of solute (mol) per liter (L) of solution. The molarity (M) can be calculated using the formula:
M = number of moles (n) /volume (V)
In this question, a 500 ml aqueous solution of Na3PO4 was prepared using 82g of the solute.
Molar mass of Na3PO4 = 23(3) + 15 + 16(4)
= 69 + 31 + 64
= 164g/mol
Mole = mass/molar mass
mole = 82/164
mole = 0.5 mol
Volume in Litres (L) = 500 ml ÷ 1000 = 0.500L
Therefore, Molarity (M) = 0.5/0.500
Molarity = 1 M or 1 mol/L
Answer: B. a chemical change
Explanation:
<span>Here are some
pH < 7
Sour taste (though you should never use this characteristic to identify an acid in the lab)
Reacts with a metal to form hydrogen gas Increases the H+ concentration in water
Donates H+ ions<span>
Turns blue litmus indicator red</span></span>
