The <span>era that is know as the age of mammals is the </span><span>Mesozoic
period.
Answer: Letter D
Hope that helps. -UF aka Nadoa</span>
Answer:
Temporary in nature.
No new substance is formed.
Explanation:
Temporary in nature: Does not affect the internal structure of a substance, only the molecules are rearranged.
No new substance is formed: Most of the physical changes are reversible. We can obtain the substance back even after the change.
hope this helps
have an awesome day -TJ
Answer:
Explanation:
What we need to do here is to determine the ratios by using the Rydberg equation starting with the transition to n1 = 1, 2,3, etc and see which one fits the data. Remember the question states that they are series and the wavelengths will be for increasing energy levels.
1/λ = Rh x ( 1/n₁² - 1/n₂²)
Lyman series ( n₁=1 and n₂= 2,3 etc) for the first two lines, the ratios will be:
1/λ₁ /1/λ₂ =(1/1 -1/ 2²) / (1/1 -1/ 3²) ⇒ 0.84 ≠ 0.74 (the first ratio)
For Balmer series n₁ = 2 and n₂ = 3,4,5, etc
1/λ₁ /1/λ₂ =(1/4 -1/3²) / (1/4 -1/4²) ⇒ 0.741 = 0.741 (match!)
Lets use the third line to check our answer:
1/λ₁ /1/λ₂ =(1/4 -1/3²) / (1/4 -1/5²) = 0.66
Answer: you will change the atom from one element to a different element. Sometimes, when you add a proton to an element, the element will become radioactive. If you change the number of neutrons in an atom, you get an isotope of the same element.
Explanation:
Answer:
Potassium is an element that has 19 electrons