Salt water is a Homogeneous Mixture......
The given question is incomplete. The complete question is:
The change in entropy is related to the change in the number of moles of gas molecules. Determine the change in moles of gas for each of the reactions and decide if the entropy increases decreases or has little to no change:
A. 
B. 
C. 
D. 
Answer: A. : decreases
B. 
: decreases
C. : no change
D. : increases
Explanation:
Entropy is defined as the randomness of the system.
Entropy is said to increase when the randomness of the system increase, is said to decrease when the randomness of the system decrease and is said to have no change when the randomness remains same.
In reaction , as gaseous reactant is changed to solid product, entropy decreases.
In reaction , as 4 moles of gaseous reactants is changed to 2 moles of gaseous product, entropy decreases.
In reaction , as 3 moles of gaseous reactants is changed to 3 moles of gaseous product, entropy has no change.
In reaction , as 1 mole of gaseous reactant is changed to 3 moles of gaseous product, entropy increases.
Answer:
1(a) N = 3
(b) N = 0
(c) N = 5
(d) N = -2
(2) Molecular formula for benzene is C6H6
Explanation:
1(a) N02 1-
N + (2×-2) = -1
N-4 = -1
N = -1+4 = 3
(b) N2
2(N) = 0
N = 0/2 = 0
(c) NO2Cl
N + ( 2×-2) + (-1) = 0
N - 4 - 1 = 0
N - 5 = 0
N = 0+5 = 5
(d) N2H4
2(N) + (4×1) = 0
2N + 4 = 0
2N = 0 - 4 = -4
N = -4/2 = -2
(2) Molcular mass of benzene = 78g/mole = (6×12g of carbon) + (6×1g of hydrogen) = 72+6 = 78g/mole
Therefore, molecular formula for benzene is C6H6
Melted rock and minerals below the earth's crust is also known as magma
Answer: C
Explanation:
According to Neils Bohr, atoms contain electrons which are arranged in energy levels. The energy levels proceed from the lowest to the highest. When energy is supplied to an atom,it moves from lower to higher energy levels. The higher energy level is known as the excited state. Excited states are short lived and atoms quickly return to ground state with emission of the absorbed energy in the form of visible light. This visible light must have one of the seven colours observed in the visible spectrum; Red, orange, yellow, indigo, blue, green, violet. Energy required for this excitation is supplied by heating the substance in a flame.
