A physical change.
Physical change = can be reverted + doesn't change substance
Chemical = changes substance
Answer:
Bleach and seawater are identified wrong.
Explanation:
Acids have an pH that is lower than 7 and bases have a pH of higher than 7 and (pH 7 is neutral)
We can observe from the table that bleach has a pH of 13 which is higher than 7 and shows basic characteristics
As for seawater the table shows it has a pH of 8 which is also a base. Therefore the answer is 3rd option "Bleach and seawater should be identified as bases".
Answer:
"Hydrogen is still available outside the core, so hydrogen fusion continues in a shell surrounding the core. The increasingly hot core also pushes the outer layers of the star outward, causing them to expand and cool, transforming the star into a red giant."
Answer:
k = -0.0525 s⁻¹
Explanation:
The equaiton for a first order reaction is stated below:
ln[A]=−kt+ln[A]₀.
[A] = 5.50 x 10⁻³ M
[A]₀ = 7.60 x 10⁻² M
t = 85.0 - 35.0 = 50.0 s
The rate constant is represented by k and can be calculated substituting the values given above:
k = (ln[A]₀ - ln[A])/t
k = (ln5.50 x 10⁻³ M - ln7.60 x 10⁻² M)/50.0s
k = -0.0525 s⁻¹
