Answer:
Chemical reaction are irreversible. Some of the example of chemical reaction are cooking, rusting, and burning. During a chemical reaction, the composition of substances changes and the particles rearrange to form a new substance. The new substance formed after chemical reaction of substance has different physical and chemical properties.
When a chemical reaction occur, the atoms or molecules of the substances change its physical and chemical properties such as while cooking of vegetable, the molecules of vegetable undergo changes in their properties and form a new substance which is different from the earlier.
Answer:
The total number of atoms is 12 + 22 + 11 = 45, so carbon atoms are 12/45 of the total.
Explanation:
–3568.0 kJ/mol * 1.411 g / 115.27 g/mol = -43.67 kJ<span>
</span>Heat capacity of the calorimeter: -43.67 kJ / 3.379 ° = <span>-12.92 kJ/deg C
</span>
Not 100% sure about my answer
<h3>Answer:</h3>
Krypton has a higher melting point than argon because of its stronger dispersion forces.
<h3>Explanation:</h3>
Dispersion forces also known as London Dispersion forces are found in non polar compounds. These interactions take place in two steps.
Step 1: Instantaneous Dipole:
In non polar compounds the electron density on atom is symmetrical. When these symmetrical atoms approaches second symmetrical atom, a disturbance in electron densities occur due to repulsion between electrons. Due to repulsion the electrons density change there position and for a small period of time and instantaneous dipole is produced on an atom.
Step 2: Induced Dipole:
The dipole produced in step one when approaches another symmetrical atom, the partial positive part (low electron density site) attracts the electron from symmetrical atom and induces polarity in it. In this way the non polar atoms become polar and interacts with each other.
<h3>Factors Effecting Strength of Dispersion Forces:</h3>
i) Size of Atom / Molecule:
Greater the size of an atom greater will be the dispersion forces and vice versa.
ii) Shape of Molecules:
Greater the branching on molecule, weaker will be the dispersion forces and vice versa.
<h3>Conclusion:</h3>
As the size of Krypton is greater than Argon therefore, it will have stronger dispersion forces and will melt at higher temperature than Argon.
Answer:
m = 19 grams
Explanation:
Given that,
No. of moles, n = 0.8
The molar mass of magnesium, M = 24.305 u
We need to find the mass of 0.80 moles of Mg. We know that given mass to the molar mass is equal to no of moles. Let the mass is m. So,
or
m = 19 grams
So, the mass of 0.8 moles of Mg is 19 grams.
