<span>The </span>standard enthalpy of formation<span> <span>is defined as the change in </span></span>enthalpy<span> <span>when one mole of a substance in the </span></span>standard<span> <span>state (1 atm of pressure and temperature of 298.15
K) is </span></span>formed<span> <span>from its
pure elements under the same conditions.</span></span>
The structural formula of carbon is as shown below. Carbon is a nonmetallic and tetravalent compound that can accommodate 4 electrons to form a covalent bond. It has the capacity to establish bonds easily with other atoms and with other carbon atoms too, carbon is competent of establishing multiple stable covalent bonds with suitable multivalent atoms.
Chemical formula = 
Answer:
D
Explanation:
The sample must contain impurity that is lower in atomic mass to sodium and since potassium has higher atomic mass to sodium, the answer is the sample contains NaCl and LiCl. We are sure already that the sample is not pure which rules out option a and option b contains sodium iodide which cannot contribute to the increase in chlorine
Answer:Group 1 elements have 1 valence electron, meaning they have 1 extra electron that can easily be donated to an atom in search of 1 more electron. When they give away that extra electron to form an ionic compound, they become more stable.
For example, Group 7A (Group 17) elements have 7 valence electrons, meaning they need 1 extra electron to be stable. Group 1 and 7A elements make splendid ionic compounds.
Explanation: