Answer:
52 da
Step-by-step explanation:
Whenever a question asks you, "How long to reach a certain concentration?" or something similar, you must use the appropriate integrated rate law expression.
The i<em>ntegrated rate law for a first-order reaction </em>is
ln([A₀]/[A] ) = kt
Data:
[A]₀ = 750 mg
[A] = 68 mg
t_ ½ = 15 da
Step 1. Calculate the value of the rate constant.
t_½ = ln2/k Multiply each side by k
kt_½ = ln2 Divide each side by t_½
k = ln2/t_½
= ln2/15
= 0.0462 da⁻¹
Step 2. Calculate the time
ln(750/68) = 0.0462t
ln11.0 = 0.0462t
2.40 = 0.0462t Divide each side by 0.0462
t = 52 da
Answer:
12.5mm
Explanation:
1cm = 10mm
so you need to multiply the 1.25 by 10 to get it in mm.
When two oxygen atoms get close to each other, the attractions from the nucleus of both atoms attract the outer electrons.
(BRAINLIEST PLEASE!!!)
<h3>
Answer: D) all of the above</h3>
Explanation:
The lungs pump oxygen in and carbon dioxide out, which goes through the blood stream to help with the cell's energy needs.
Nutrients pass through the blood stream as well. The nutrients start with the digestive system (mouth, esophagus, stomach, small intestine) before going into the blood stream. The nutrients are building blocks to help make new cells when old ones die off.
When those cells die off, the body sheds them like dead skin, but internal dead cells are passed off as waste. This waste and other byproducts the body doesn't need passes through the blood stream as well.
In short, the blood stream is basically the highway to help get desired materials (eg: oxygen and nutrients) and get rid of waste (eg: carbon dioxide and other unwanted byproducts or dead cell material)
So that's why the answer includes A, B and C.
Answer:
D
Explanation:
wavelength = speed of light/ frequency
= (3 x 10^8 m/s) / (3 x 10^12 Hz)
= 1 x 10^-4 m