Answer:
2Mg + 2CO₂ → 2MgO + C
Option a.
Explanation:
The chemical reactions are balanced in order to verify compliance with the Law of conservation of mass. This law states that in any chemical reaction, the mass of the reagents must be equal to the mass of the products
The first one.........................
Explanation:
Groups are numbered 1–18 from left to right. The elements in group 1 are known as the alkali metals; those in group 2 are the alkaline earth metals; those in 15 are the pnictogens; those in 16 are the chalcogens; those in 17 are the halogens; and those in 18 are the noble gases.
Answer:
5. Atoms with high ionization energies and high electron affinities have low electronegativities.
Explanation:
Ionization energy is the minimum amount of energy which is required to knock out the loosely bound valence electron from the isolated gaseous atom.
Electron affinity is the amount of energy released when an isolated gaseous atom accepts electron to form the corresponding anion.
Electronegativity is the tendency of an atom in a bond pair to attract the shared pair of electron towards itself.
Low ionization energies as well as low electron affinities mean the atom has low effective nuclear charge, which results in the less attraction of the valence electrons by the atom and thus, low electronegativity.
Answer:
3 hours
Explanation:
To know the the correct answer to the question given above, it is important we know the definition of half-life.
The half-life of a substance is simply defined as the time taken for half the substance to decay.
Considering the diagram given above, the initial mass of the substance is 100 g.
Half of the initial mass = 100 / 2 = 50 g
Now, we shall determine the time from the graph taken to get to 50 g.
Considering the diagram given above, the time taken to get to 50 g is 3 hours.
Therefore, the half-life of the material is 3 hours.
