Answer: 
Explanation:Bond energy of H-H is 436.4 kJ/mole
Bond energy of C-H is 414 kJ/mol
Bond energy of C=C is 620 kJ/mol
Bond energy of C≡C is 835 kJ/mol

= {1B.E(C≡C)+2B.E(C-H) +1B.E(H-H)} - {1B.E(C=C)+4B.E(C-H)}


Answer:
Tempreture should be the correct answer!!
Explanation:
hope this helps ya!!
Answer : The given compound belongs to ether and alcohol.
Explanation :
The chemical formula of the given compound is, 
First we have to calculate the degree of unsaturation.
Formula used:
Degree of unsaturation = 
where,
C = number of carbon
H = number of hydrogen
N = number of nitrogen
X = number of halogen
Degree of unsaturation = 
The degree of unsaturation is, 0 that means there is no double or triple bond in the compound only single bond is present between the atoms.
Thus, the given compound belongs to ether and alcohol.
The head of the phospholipids molecule is attracted to water, the tail repels water
The correct answer is:
A positively charged nucleus is surrounded by one or more negatively charged electrons
The explanation:
when:
proton is a positively charged elementary particle that is a fundamental constituent of all atomic nuclei.
neutron is a subatomic particle found in the nucleus of every atom except that of simple hydrogen. The particle derives its name from the fact that it has no electrical charge
electron is a negatively charged subatomic particle. It can be either free (not attached to any atom), or bound to the nucleus of an atom .
so, , there are positively charged protons and zero-charged neutrons in the nucleus of an atom. Therefore, the nucleus is positively charged, Surrounding the nucleus, the electrons have negative charge.
Thus, the correct answer is (3): A positively charged nucleus is surrounded by one or more negatively charged electrons is correct.