Answer: The p orbital can hold up to six electrons. We'll put six in the 2p orbital and then put the remaining electron in the 3s. Therefore the sodium electron configuration will be 1s22s22p63s1.
Explanation:
Answer:
The correct answer is <em>C) Two atoms of silver are needed to complete the reaction.</em>
Explanation:
The Law of Conservation of Matter postulates that "the mass is not created or destroyed, only transformed." This means that the reagents interact with each other and form new products with physical and chemical properties different from those of the reagents because the atoms of the substances are ordered differently. But the amount of matter or mass before and after a transformation (chemical reaction) is always the same, that is, the quantities of the masses involved in a given reaction must be constant at all times, not changing in their proportions when the reaction ends.
Then, taking into account the Law of Conservation of Matter, as an atom cannot be created or destroyed in a chemical reaction, the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products.
For this, the chemical equation must be balanced. For that, you must first look at the subscripts next to each atom to find the number of atoms in each compound in the equation. If the same atom appears in more than one molecule, you must add its quantities. On the other hand, the coefficients located in front of each molecule indicate the amount of each molecule for the reaction. This coefficient can be modified to balance the equation, just as you should never alter the subscripts. By multiplying the coefficient mentioned by the subscript, you get the amount of each element present in the reaction.
In this case:
Left side: 2 silver (Ag), 2 hydrogen (H) and 1 sulfur (S)
Right side: 2 silver (Ag), 2 hydrogen (H) and 1 sulfur (S)
In this case the equation is balanced because you have the same amount of all the elements on each side of the reaction. And <u><em>the 2 in front of 2Ag indicates that,since silver is a reagent, two atoms of silver are needed to complete the reaction. (option C).</em></u>
Answer:
Elements having same valence electrons are placed in <u>same group.</u>
Explanation:
First, let's start with some basic concepts of modern periodic table:
1. Modern Periodic table : It is the arrangement of element in the increasing order of their atomic numbers
The Modern periodic table is divided into Periods and groups .
Periods : These are the horizontal rows. There are seven periods in the periodic table . Period 1 has 2 element. Period two and three has 8 elements , period 4 and 5 have 18 elements and the period 6 and 7 have 32 elements.
Same period have same number of atomic orbital(Shell)
Group : The group is the vertical columns . There are 18 groups in the modern periodic table.Those element which have same group number will also have same number of electron in their outermost shell. The number of electron in the outermost shell determines the valency of the element.
So, elements showing same valency are placed in same group.
All alkali are place in group 1 and have 1 valance electron in the outermost shell
