Since the number of moles of a substance is the mass divided by the molar mass of the substance, we can just simply multiply the molar mass of magnesium chloride by the number of moles, which is 4.40 in this case.
To find the molar mass, refer to the periodic table for the relative atomic mass of Mg and Cl and add them together. Since there’s 2 chloride ions in MgCl2, double the relative atomic mass of Cl when adding.
24.31 + 35.45x2
=95.21
Now just multiply 95.21 to 4.40mol, which you’ll get 418.9g (corrected to 3 significant figures)
<h2>Enthalpy Difference</h2>
Explanation:
- The 2nd Law of Thermodynamics states that when energy is converted from one form to another, some is always lost due to difference in the enthalpy of the system, which always increases.
- Enthalpy may be defined as the amount of energy that is stored.
- During a chemical reaction, the system will absorb or gives out energy in the form of heat and light.
- The change in energy during a chemical reaction is due to the difference in the energy amount of reacting species and species that are formed.
Answer: the correct answer is B. Hallogens hope this helped mind helping out with making me brainliest?
Answer:
A
Explanation:
A catalyst refers to an enzyme composed of peptides in their tertiary conformation.
The addition of a catalyst provides a new path to the reaction and the reaction proceeds in a faster way compared to the reaction without a catalyst.
The peptides are arranged in such a way that they form a pore-like structure which allows the binding of the substrate molecules by forming a temporary covalent bond. These bonds lower the activation energy of the complete reaction which is required to initiate a reaction.
In the given diagram, the activation reaction is represented by the letter "A" and therefore a catalyst will lower and alter the value of A.
Thus, Option-A is correct.
Answer: The student’s values are accurate as well as precise.
Explanation:
Precision refers to the closeness of two or more measurements to each other.
For Example: If you weigh a given substance three times and you get same value each time. Then the measurement is very precise.
Accuracy refers to the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 50 kg and one person weighed 49 kg and another person weighed 48 kg. Then, the weight measured by first person is more accurate.
Given: Mass = 5.000 g
Mass weighed by A has values 4.891 g , 4.901 g and 4.890. Thus the average value is 
Thus as the measured value is close to the true value, the student’s values are accurate and as the values are close to each other, the measurement is precise.
