Nitrous acid is HNO2. Its dissociation is HNO2 = H(+) + NO2(-). The equilibrium constant, Ka = [H+][NO2-]/[HNO2] => x^2 / (0.20 - x). Given that it is a weak acid (Ka = 4.6 * 10^ -4),you can use a very good approxiamation: 0.20 >> x => 0.20 - x = 0.20, and this permits you to solve the value of x more easily. => 4.6 * 10^-4 = (x^2) / 0.20 => x^2 = 0.20 * 4.6 * 10^ -4 = 0.92 * 10^-4 => x = 9.59 * 10^ -3. Now,calculate pH = log { 1 / [H+] } = log { 1 / (9.59 * 10 ^-3) } = 2.02. <span>Answer pH = 2.02</span>
Answer:
The answer is 380.
Explanation:
Significant figures:
All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.
Leading zeros are not consider as a significant figures. e.g. 0.06 in this number only one significant figure present which is 6.
Zero between the non zero digits is consider significant like 108 consist of three significant figures.
The zeros at the right side e.g 6300 are also significant. There are four significant figures are present.
How to round the value to three significant figures.
First of all we will place the vertical line after 3rd digit.
379/5
Now we will look at the 4th digit. If it is five or more than five then one is added to 3rd digit. If it is less than five the 3rd digit remain same. In given value 4th digit is 5 thus one is added into 9 and the value become 380.
The answer is 380.
Answer:
The correct answer is "increase; faster".
Explanation:
The kinetic energy is defined as the power that an object has result of its movement. The kinetic energy of a substance has a direct relation with the temperature. As the temperature rises, the kinetic energy of the molecules increases, result of an increase in the speed of its movement. A higher temperature causes that the particles vibrate faster, which increases the kinetic energy.
Hey there!:
Number of moles = ( number of atoms / 6.023*10²³ atoms )
given number of atoms = 5.03*10²⁴
Therefore:
Number of moles B = 5.03*10²⁴ / 6.023*10²³
Number of moles B = 8.35 moles
Hope that helps!
<span>7.2 g of water.
This is a simple matter of adding up the masses of the initial reactants and determining the mass of the results. You started with 3.2 g of methane and 12.8 g of oxygen. So the total mass you start with is 3.2 + 12.8 = 16.0 grams. The reaction results in water and carbon dioxide. The mass of the carbon dioxide is 8.8 g, so the mass of the water will be 16.0 - 8.8 = 7.2 g.</span>
