Answer:
3.6 × 10⁻⁵ M
Explanation:
Ergosterol has a maximum absorbance at λ = 282 nm. The absorbance of an analyte is related to its concentration through the Beer-Lambert's law.
A = ε × <em>l</em> × c
where,
A: absorbance
ε: molar absorptivity
<em>l</em>: optical path length
c; molar concentration
c = A / ε × <em>l </em>= 0.43 / (11,900 M⁻¹cm⁻¹) × 1.00 cm = 3.6 × 10⁻⁵ M
Answer:
Data obtained can't be accurate.
Explanation:
A beaker can't be used for measuring the volume of a liquid because they did not calculate volume of a liquid accurately and precisely. The marks present on the beaker are not accurate, it is just an estimate so by measuring the volume of any liquid using beaker give us a false data so that's why beaker are not used for the measurement of a volume.
To calculate the molarity you only need to know the number of moles in the solution and the volume of that solution. This exercise gives both and with that you divide moles by volume(usually in liters).
500 ml equals 0,5 L
molarity= number of moles/ volume
molarity=0,75 x 0,5
= 0,375 mol/L
Answer:
B.) If sodium carbonate is added to vinegar, the reaction will absorb heat.
Explanation:
A.) is incorrect because this is not testable. Rather, it is just an opinion that cannot be proven correct or incorrect.
B.) is correct because this statement is testable. Tests need to be run to determine the accuracy of the statement.
C.) is incorrect because this statement explains something that does not need to be tested. It is an example of a physical change when one tears a piece of paper.
D.) is incorrect because this is already a true statement. It is obvious that not all reactions absorb/release heat. While tests could be run to further prove this statement true, it is already considered accurate.
<span>Very quick oxidation reactions result in combustion. Combustion happens when oxidation is fast. An example of combustion is the light batteries. We know that it is really dangerous if we will burn it because it has a fast oxidation process that can cause fire and its gas will explode.</span>