Answer:
banging rocks together to see which make make a spark and create fire painting pictures is an example of art and sleeping in caves is survival
<span>During an experiment, given that other elements that make up the compound are identified, an unknown element x can easily make separate if certain properties of that unknown element is exhibited in the experiment. So, the first thing to do would be to identify the compound, identify and isolate all the knowns and one can test to see the properties which the unknown element is giving and make a reasonable deduction from that.For example if we were testing for the presence of water in Copper(II) sulfate . if water is in the sample that we were testing for, we will see that the sample will turn blue because of the presence of water</span>
Answer:
D +405.0kJ mol-¹
Explanation:
Since bond energy is the energy required to break a bond, the energy of dissociation of X₂H₆ = +2775 kJmol⁻¹.
Since there is one X-X bond and six X-H bonds,
Bond energy of one X-X bond + Bond energy of six X-H bonds = energy of dissociation of X₂H₆.
Since bond energy of one X-H bond = 395 kJ mol⁻¹, then
Bond energy of one X-X bond + Bond energy of six X-H bonds = energy of dissociation of X₂H₆
Bond energy of one X-X bond + 6 × one X-H bond = +2775 kJmol⁻¹.
Bond energy of one X-X bond + 6 × 395 kJ mol⁻¹ = +2775 kJmol⁻¹.
Bond energy of one X-X bond + 2370 kJ mol⁻¹ = 2775 kJmol⁻¹
Bond energy of one X-X bond = 2775 kJmol⁻¹ - 2370 kJ mol⁻¹
Bond energy of one X-X bond = +405 kJmol⁻¹
