Answer:
(b). Mass and distance.
Explanation:
The gravitational force between two objects is given by Newton's law of universal gravitation. The formula is as follows :
Here,
G is universal gravitational constant
r is the distance between two objects
It is very clear that the gravitational force is directly proportional to the product of masses and inversely proportional to the square of the distance between them.
Hence, the two quantities are used to predict gravitational force according to Newton's law of universal gravitation are mass and distance.
Answer: chemical
Explanation: whenever heat is applied, it indicates a chemical change
Answer:
solid silver chloride forms along with a new liquid, sodium nitrate
Explanation:
Answer: only Br2.
Justification.
In a chemical reaction the element that gains electrons experiments a reduction in its oxidation state, that is why it is said that it is reduced.
So, to know what element is being reduced you need to calculate the oxidation states of the elements involved.
Here I indicate the oxidation states of each element if the reaction putting them inside parenthesis:
Reactants side Products side
K (0) K (1+)
Br (0) Br(1-)
So, K lost one electron, increasing its oxidation statefrom 0 to 1+, meaning that it is being oxidized.
And, each atom of Br gained one electron, reducing its oxidation state from 0 to 1-, meaning it is being reduced.
Therefore, the answer is that Br2 is the substance being reduced.
Answer:
3 hours
Explanation:
To know the the correct answer to the question given above, it is important we know the definition of half-life.
The half-life of a substance is simply defined as the time taken for half the substance to decay.
Considering the diagram given above, the initial mass of the substance is 100 g.
Half of the initial mass = 100 / 2 = 50 g
Now, we shall determine the time from the graph taken to get to 50 g.
Considering the diagram given above, the time taken to get to 50 g is 3 hours.
Therefore, the half-life of the material is 3 hours.
