The atomic structure of the atom contains 9 positively charged particles (protons) and 10 neutrally charged particles (neutrons) in the center of the atom in a clump called the nucleus. Those 9 negatively charged particles (electrons) are moving around outside of the nucleus.
There are 10 neutral charges, because the mass of 19 comes from the number of neutral charges plus the number of positive charges.
To calculate the number of neutral charges, subtract the positive charges from the mass (19 - 9), and you get the number of neutral charges (10).
The third option because the elements mentioned in that selection are in the same group, they must have similar properties.
If the Kelvin
temperature of a gas is doubled, the volume of the gas will increase by two. It
follows Charles law where in for a mixed gas of mass, the volume is directly
proportional to the temperature at constant pressure.
Answer:
-23.333 °C
Explanation:
(-10°F − 32) × 5/9 = -23.33°C
By using the formula, mass = density x volume, we
calculate mass in grams
20.0 mL CH₃COOH x (1.05 g / mL) = 21.0
g CH₃COOH
To find the moles, molar mass of CH₃COOH = 60.05g/mol<span>
21.0 g </span>CH₃COOH x (1 mole CH₃COOH / 60.05 g CH₃COOH)
= 0.350 moles CH₃COOH
To find molarity,<span>
[</span>CH₃COOH] = moles CH₃COOH / L of solution = 0.350 /
1.40 = 0.250 M CH₃COOH<span>
When </span>CH₃COOH is dissolved in water, it produces
small and equal amounts of H₃O⁺+ and C₂H₃O₂⁻.
<span>
Molarity , </span>CH₃COOH<span> + H</span>₂O <==> H₃O⁺ + C₂H₃O₂⁻
<span>
<span>Initial 0.250 0 0 </span>
Change -x x x
Equilibrium 0.250-x x x
K</span>ₐ = [H₃O⁺][C₂H₃O₂⁻] / [HC₂H₃O₂] = (x)(x) /
(0.250-x) = 1.8 x 10⁻⁵
<span>Since K</span>ₐ is relatively small, we can neglect the -x
term after 0.250 to simplify
<span>x</span>² / 0.250 = 1.8 x 10⁻⁵
x² = 4.5 x 10⁻⁶
<span>
x = 2.1 x 10</span>⁻³<span> = [H</span>₃O⁺]
pH = -log [H₃O⁺] = -log (2.1 x 10⁻³) = 2.68
