Answer:
the HOMO-LUMO energy difference in ethylene is greater than that of cis,trans−1,3−cyclooctadiene
Explanation:
The λmax is the wavelength of maximum absorption. We could use it to calculate the HOMO-LUMO energy difference as follows:
For ethylene
E= hc/λ= 6.63×10^-34×3×10^8/170×10^-9= 1.17×10^-18J
For cis,trans−1,3−cyclooctadiene
E= hc/λ=6.63×10^-34×3×10^8/230×10^-9=8.6×10^-19J
Therefore, the HOMO-LUMO energy difference in ethylene is greater than that of cis,trans−1,3−cyclooctadiene
Answer : The time passed in years is 
Explanation :
Half-life = 5730 years
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the time passed.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = time passed by the sample = ?
a = let initial amount of the reactant = X g
a - x = amount left after decay process = 
Now put all the given values in above equation, we get


Therefore, the time passed in years is 
The molecular weight of water is <span>18.01528 g/mol.
So in 2.92 grams there are 2.92/</span>18.01528 = 0.1621 mol of particles.
1 mol contains 6,02214 × 10^<span>23 particles by definition.
So the nr of H2O molecules is </span>0.1621 * 6,02214 × 10^23 = 0,9761 × 10^23.
Every molecule has 2 H atoms, so you have to double that.
2* 0,9761 × 10^23 = 1.952 × 10^23.
Answer:
B. Carry oxygen, nutrients, waste, & to fight pathogens
Explanation:
The circulatory system refers to all organs and tissues involved in carrying blood and lymph around the body.
The circulatory system carries oxygenated blood from the heart to cells and deoxygenated blood back to the heart.
Nutrients are carried in the blood to cells in different parts of the body and waste products are also carried from cells in the blood.
White blood cells is a component of blood in the circulatory system that fights off diseases.
the formula of the heavy water is D2O