<span>Answer: 5.32 x 10⁻³ M
Explanation:
1) The rate law for a first order reaction is:
</span><span />
<span>r = - d [A] / dt = k[A]
</span><span />
<span>2) When you integrate you get:
</span><span />
<span> [ A] = Ao x e ^(-kt)
</span><span />
Remember that here A is PH₃
<span>3) Plug in the data: Ao = 0.0316M, k = 0.0180 /s, and t = 99s
</span><span />
<span>[PH₃] = 0.0316 M x e ^( - 0.0180/s x 99s) = 5.32 x 10⁻³ M</span>
A. The mass of one mole of the virus is calculated by multiplying the mass of a single virus by the Avogadro's number which is equal to 6.022 x 10^23. Performing this operation,
mass = (9.0 x 10^-12 mg)(6.022 x 10^23) = 5.42 x 10^12 mg
In correct number of significant figures, the answer would only have to be 5.4 x 10^12 mg.
b. The number of moles of the virus that will have the same mass as the oil tanker is calculated by dividing the mass of the oil tanker by the mass of one mole of the virus. Note that doing division, both would have to have the same units.
n = (3.0 x 10^7 kg) / (5.4 x 10^12 mg)(1 g/1000 mg)(1 kg/1000 g)
Simplifying,
n = 6
In correct number of significant figures, the answer is 6.0.
Answer:
a. very acidic
Explanation:
A solution with a pH of 1.6 would be described as a very acidic solution.
The pH scale is a convenient scale for expressing the level of acidity or alkalinity of aqueous solutions.
The scale ranges from 1 to 14 in which case 1 is the lower limit and 14 the upper limit.
- An acidic solution has a pH value less than 7. As pH decreases, the acidity of the solution increases.
- Neutral solutions have a pH of 7
- An alkaline solution has a pH greater than 7 and the level of alkalinity increases as pH increases.
Answer: The element with an atomic number of 13 is <em>aluminum</em>. It belongs in <em>group 13 (the boron group). </em>It belongs in <em>period 3</em>.
Answer:
her results has good precision
Explanation:
accuracy and precision