Answer:
NaCl + Fe2+ ---> FeCl2 + Na+
Single replacement
Explanation:
Na is replaced by Fe2+ to form FeCl2, and that is the only replacement. Thus, it is single replacement.
The 2 hormones are insulin & glucagon.
A hormone will only act on a part of the body it 'fits'. A hormone can be thought of as a key, and its target site ( i.e an organ) has specially shaped locks on the cell walls.
If the hormone fits, then it will work.
The hormone can set off a cascade of other singling pathways in the cell to cause an immediate effect ( for instance, insulin signaling leads to a rapid uptake of glucose in muscle cells)
The endocrine system is a tightly regulated system that keeps the hormones and their effects at just the right level. One way this is achieved is through ' feedback loops'. The release of hormones is regulated by other hormones, proteins or neuronal signals.
The released hormone then has its effect on other organs. This effect on the organ feeds back to the original signal to control any further hormone release.
btw- found all this info @ the Better Health channel, an australian government health website , so if your still confused by my answer, check out this website
www.betterhealth.vic.gov.au/health/conditionsandtreatments/hormonal-endocrine-system
This would be 8.010 * 10^-2
Combustion reaction for menthol is as follows;
CxHyOz + O₂ ---> xCO₂ + H₂O
Mass of CO₂ formed - 28.16 mg
Therefore number of moles formed - 28.16/ 44 g/mol = 0.64 mmol
Mass of water formed - 11.53 mg
number of water moles formed - 11.53 mg/18 g/mol = 0.64 mmol
From CO₂,
1 mol of CO₂ - 1 mol of C and 2 mol of O
therefore number of C moles - 0.64 mmol
O moles - 1.28 mmol
from H₂O
1 mol of H₂O - 2 mol of H and 1 mol of O
number of H moles - 1.28 mmol
O moles - 0.64 mmol
Mass of menthol initially - 10 mg
in reactions, the masses of products are equal to the masses of reactants. The excess mass to the products formed is due to O₂ in air
Original mass of menthol - 10 mg
mass of water and CO₂ - 11.53 mg + 28.16 mg = 39.69
Difference in mass - 39.69 - 10 = 29.69 mg
This difference comes from O moles in air - 29.69 mg/ 16 g/mol = 1.8556 mmol
then O moles coming from menthol - (1.28 + 0.64) - 1.8556 = 0.064 mmol
In menthol
C moles - 0.64 mmol
H moles - 1.28 mmol
O moles - 0.064 mmol
ratios of C:H:O
C H O
0.64 1.28 0.064
x1000 x1000 x1000 to get whole numbers
640 1280 64
10 20 1
Simplest ratio of C:H:O is 10:20:1
therefore empirical formula of menthol is C₁₀H₂₀O
Answer is: ph value of pyridine solution is 9.1.
Chemical
reaction: C₅H₅N +
H₂O → C₅H₅NH⁺ + OH⁻.<span>
c(pyridine - C</span>₅H₅N)
= 0.115M.<span>
Kb(C</span>₅H₅N)
= 1.4·10⁻⁹.
[C₅H₅NH⁺] = [OH⁻] = x; equilibrium concentration.<span>
[</span>C₅H₅N] =
0.115 M - x.
Kb = [C₅H₅NH⁺] · [OH⁻] / [C₅H₅N].
1.4·10⁻⁹ = x² / (0.115 M -x)
Solve quadratic equation: x = [OH⁻] = 0.0000127 M.<span>
pOH = -log(0.0000127 M) = 4.9</span>
<span>pH = 14 - 4.9 = 9.1.</span>
