Answer:
A reversible reaction is one where <u><em>B) there is little change in the net free energy between substrate and product.</em></u>
Explanation:
A reversible reaction is one that reagents are transformed into products and at the same time products are transformed into reagents. That is to say that as the products appear in the reaction, they can react with each other by regenerating the reagents again. It is represented by a double arrow, indicating that the reaction can be carried out both in one direction and the other way around.
At the start of the reaction, there is a large amount of reagents. As time goes by, that amount decreases and speed too.
On the other hand, at the beginning of the reaction there are no products. As the reaction happens, the products are being formed and their speed will increase to match the speed of the reagents. When the rates of products and reagents are equal and constant, it is possible to say that the reaction is in chemical equilibrium. At this point, both reactions continue to happen, but the total concentrations of reagents and products no longer change.
The Gibbs free enthalpy or free energy of a system is a measure of the amount of usable energy (energy that a job can perform) in that system.
When a reaction system is in chemical equilibrium, it is in the lowest possible energy state (it has the lowest possible free energy). If a reaction is not in equilibrium, it will move spontaneously towards it because that allows it to reach a state of lower and more stable energy. Then when the reaction moves towards equilibrium, the free energy of the system decreases more and more.
Finally, <u><em>a reversible reaction is one where B) there is little change in the net free energy between substrate and product.</em></u>
litmus paper
Because it will just tell if the solution is acidic or basic, it won't tell the pH
Answer:
OPTION (A) : Testing a rock sample for gold content
Explanation:
For testing a rock sample of gold content you will need a Chemist. To test the material, the sample is rubbed on black stone which will leave a mark on the stone. This mark is tested by applying aqua fortis i.e nitric acid on the mark. If the mark gets dissolve then the material is not gold. If the mark sustain the it is further tested by applying aqua regia i.e nitric acid and hydrochloric acid which will prove the sample is of gold if it gets dissolve on using hydrochloric acid. The purity of the sample can be checked by differing the concentration of the aqua regia and comparing it with the gold material of the known purity.
Answer : The mass of sample is, 267.5 grams.
Explanation :
Density : It is defined as the mass of a substance contained per unit volume.
Formula used :
Given:
Volume of Pb = 
Density of Pb = 
Now put all the given values in the above formula, we get the mass of Pb.
Therefore, the mass of sample is, 267.5 grams.
