Answer:
B
Explanation:
Chemical changes would mean changes that does not change in the form of matter.
A) water freezing in a pond is liquid to solid, so form of matter change, so it cannot be this one.
C) A tree buming is solid to gas, so form of matter change, so it cannot be this one.
D) Steam rising from pavement is solid to gas, so for of matter change, so it cannot be this one.
On the other hand B, the matter stays in the same form, solid.
Tree branch to a tree branch.
Generally speaking, acidic soil, with a pH lower than 6.0, yields blue or lavender-blue hydrangea blooms. Alkaline soil, with a pH above 7.0, promotes pinks and reds. With a pH between 6 and 7, the blooms turn purple or bluish-pink. To lower your pH, add garden sulfur or aluminum sulfate to your soil.
The secret's in the soil
Let’s look at why pH is so important.
Most major plant nutrients are more accessible at a pH of 6 to 6.5. A pH that is too high or too low can keep plants from absorbing nutrients from the soil. The nutrients are unavailable — or not absorbable — to the plant because of soil's chemistry. This problem can manifest itself in a variety of ways, but in the case of hydrangeas, the bloom color changes.
Color variation in hydrangeas is due to the presence or absence of aluminum compounds in the flowers. If aluminum is present, the color is blue. If it is present in small quantities, the color is variable between pink and blue. If aluminum is absent, the flowers are pink.
Hey there!:
V1 = 3.05 L
V2 = 3.00 L
P1 = 724 mmHg
P2 = to be calculated
T1 = 298 K
T2 = 273 K
Therefore:
P1*V1 / T1 = P2*V2 / T2
P2 = ( P1*V1 / T1 ) * T2 / V2
P2 = 724 * 3.05 * 273 / 298 * 3.00
P2 = 602838.6 / 894
P2 = 674.31 mmHg
1 atm ----------- 760 mmHg
atm ------------- 674.31 mHg
= 674.31 * 1 / 760
= 0.887 atm
Hope this helps!
