Answer:
B. Halogen
Explanation:
Halogens are the family of chemical elements found in the group VIIA of the periodic table which means they possess seven (7) outer electrons. Some examples of halogens are Fluorine (F), Iodine (I), Bromine (Br), and Chlorine (Cl).
A halogen, or an element located in group 7A, will form a salt when reacted with a metal atom.
For example, when Chlorine reacts with Sodium it would form a salt known as Sodium Chloride.
Na + Cl ----> NaCl
Answer
:
Flammable substances
Explanation
:
<em>Flammable substances</em> will catch fire and continue to burn when they contact an ignition source like a spark or a flame.
For example, <em>methanol</em> is a flammable liquid.
A flammable solid may also catch fire through friction. <em>Matches</em> are flammable solids.
Supercooling<span>, a state where liquids do not solidify even below their normal freezing point. Means sometimes we have liquid water below 0 degree C.</span>
Answer:
-2.86x10³ kJ
Explanation:
The enthalpy of a reaction (ΔH) is defined as the heat produced or consumed by a reaction. In the reaction:
2 C₂H₆(g) + 7 O₂(g) → 4 CO₂(g) + 6 H₂O(g)
The ΔH is the heat envolved in the reaction per 2 moles of C₂H₆. 1.43x10³ kJ are involved when 1 mole reacts. Thus, when 2 moles react, involved heat is:
1.43x10³ kJ ₓ 2 = <em>2.86x10³ kJ</em>. As the reaction is a combustion reaction (Produce CO₂ and H₂O), the heat involved in the reaction is <em>PRODUCED, </em>that means ΔH is negative, <em>-2.86x10³ kJ</em>
Its hydrogen atom is a high conductor of electricity
