Answer:
Solar eclipse
Explanation:
A solar eclipse occurs when a portion of the Earth is engulfed in a shadow cast by the Moon which fully or partially blocks sunlight. This occurs when the Sun, Moon and Earth are aligned. Such alignment coincides with a new moon indicating the Moon
Answer:
Gravity
Explanation:
All matter exerts a force, which is called , that pulls all other matter towards its center. The strength of the force depends on the mass of the object: the Sun has more gravity than Earth, which in turn has more gravity than an apple. Also, the force weakens with distance. Objects far from the Sun won’t be influenced by its gravity.
The answers to you questions are 3,66 g of liquid water and 0,84 g of vapor.
Solution:1) Q₁ = mxCxΔT = 4,5 g x 2,108 J/°C x g x 10°C.
= 97,86 J heat required to warm the ice to 0°C.
2) = 4,5 g x 334 J/g. = 1503 J heat required to melt the ice to water at 0°C.
3) = 4,5 g x 4,184 J/°C x g x 100°C
= 1882,28 J heat required to warm the water from 0°C to 100°C. = 5400 J - 3483,14 J = 1916,86 J heat left to vaporize the water.
mass of the vapor= 1916,86 J ÷ 2257 J/g
= 0,84 g.
Answer: Thus 3 half lives have taken place.
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.


Number of half lives =
Thus 3 half lives have taken place.