Positive or negative charge
A polyatomic ion is a cluster of covalently bonded atoms with a positive or negative charge that acts as a unit.
A polyatomic ion is a covalently bonded groups of atoms that acts as a single unit and has a positive or negative charge as a result of the formation of an ionic bond with another ion. An example of a polyatomic ion is hydroxide ion which has the chemical formula; OH− (has a charge of −1), and is made up of one oxygen atom and one hydrogen atom.
Although coal and diamonds are both composed of carbons alone, they differ in their properties because of the bonds present in each substance. Diamonds are composed of covalent bonds which are strong and is crystalline in nature which makes it sturdier. Coal is amorphous which allows the slipping of irregular layers to each other making coal brittle
Answer:
The sum of first 30 terms of the arithmetic progression is <u>2160.</u>
Explanation:
For an arithmetic progression, the sum of first 
terms with first term as 
and common difference 
is given as:
Now, it is given that:
Now, plug in these values and frame two equations in 
Now, we solve equations (1) and (2) for . Subtract equation (1) from equation (2). This gives,
Now, plug in the value of 
in equation (1) and solve for .
Plug in the values of 
in the sum formula to find the sum of first 30 terms.
Now, the sum of first 30 terms is given as:
Therefore, the sum of first 30 terms of the arithmetic progression is 2160.
There are 17 nonmetals on the periodic table of elements.
I think it is A correct me if i am wrong hope this helps
