Halogens are a group of elements consisting of Fluorine, Chlorine, Bromine, Iodine and Astatine. In their ionic form, they have a superscript of -1, for example, chloride ion is Cl-1. These means that they readily accept one electron in order to achieve the Octet rule. The Octet rule states that each atom must contain 8 electrons in their valence shell for it to be stable. The most stable set of elements are the noble gases. Because they already fulfill the Octet rule, they no longer take part in reactions. Halogens are also very electronegative, meaning, they attract more electrons toward them. This is also a consequence of the Octet rule.
From the choices, the answers would be:
<span>they require only one electron to complete their outer shell
they have a high electronegativity</span>
The concentration of hydrogen can be shown as:
[H+ ] = 3 * 10-5 M
pH can be determined as:
pH = - log [H+ ]
= - log (3 * 10-5)
= 4.53
Thus the pH of solution is 4.53
6840 is the answer hope this help
Answer:
The bottom layers of the rock could have formed before life occurred.
Explanation:
The bottom layers of the rock could have formed before life occurred because there is no fossil is present. If there is life at that time so the fossils are present at the bottom layer so the absence indicates that is no life present at that time. The bottom layer is older than the upper layer so that's why fossils of bacteria are found in the upper layer of the rock.
Answer:
C. Because bacterial fossils are found only in the upper layers, scientists can conclude that these bacteria evolved towards the end of Precambrian time.
There’s two different types of answers for this question so I just put both of them. Hope it helps : )
If we have two gram produce 2 grams were consumed
Due to the mass conversation law which state that the mass in a isolated is neither created nor destroyed by chemical reaction or physical transformation. Therefore the mass of the product must be equal to the mass reactant
