I do not agree with the statement.
The "substance" can be a compound. It's "pure"
as long as there's nothing else in it but its name.
'Pure' water is 100% H₂O with nothing else in it.
'Pure' table salt is 100% NaCl with nothing else in it.
'Pure' carbon dioxide is 100% CO₂ with nothing else in it.
These example substances are all compounds, not elements.
Dementia is a brain disease that causes a decline in memory and cognitive functioning at a much more rapid rate that is expected due to normal aging. There is no known cure and no set age that dementia can occur, but roughly 10% of people will develop it at some point in their lives. It typically affects older people and about 50% of people over 85 have dementia.
Acetic acid is a weak acid and sodium hydroxide is strong base. Salts of the two will hydrolyse to give basic solution. So, at neutral point, pH of the solution will be greater than 8.
Answer:
sweeps out equal areas in equal times.
Explanation:
As we know that there is no torque due to Sun on the planets revolving about the sun
so we will have

now we have

now we also know that

so rate of change in area is given as

so we will have


since angular momentum and mass is constant here so
all planets sweeps out equal areas in equal times.
Answer:
The question is somewhat vague in that acceleration is not exactly defined:
Usually a = (v2 - v1) / t which would imply that
a = 32 / g = 32 / 9.8 = 3.27 the acceleration due to change in speed of the rocket
One can also say that the astronaut experiences an acceleration of 9.8 m/s^2 just by being motionless on the surface of the earth.
Then a = (32 - 9.8) / 9.8 = 2.27 due to the acceleration of the rocket
If we assume the first condition then
F = 65 kg * 3.27 * 9.8 m/s^2 = 2083 N