Kepler's Law of Planetary Motion consists the movement of planets in the universe
if not? what are the four or three answers for me to answer?
"<span>using shaving cream, rather than shaving on dry skin" I believe this is the answer. coz rest of them would increase friction rather than decrease</span>
The molecular formula of sucrose is - C₁₂H₂₂O₁₁
molecular mass of sucrose - 342 g/mol
molarity of sucrose solution is 0.758 M
In 1 L solution the number of sucrose moles are - 0.758 mol
Therefore in 1.55 L solution, sucrose moles are - 0.758 mol/L x 1.55 L
= 1.17 mol
The mass of 1.17 mol of sucrose is - 1.17 mol x 342 g/mol = 4.00 x 10² g
Answer: a) 
b) 
c) 
d) 
Explanation:
General representation of an element is given as:_Z^A\textrm{X}
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
In an atom, when neutrons or protons are lost or gains, it directly affects the mass number of an atom.
Atomic number is defined as the number of protons or number of electrons that are present in an atom.
It is characteristic of a particular element.
Atomic number = Number of electrons = Number of proton
a) Z 74, A 186: 
b) Z 80, A 201: 
c) Z 34, A 76: 
d) Z 94, A 239.: 