What are important question in number system and polynomials class 9.

state of any element:

(1) The total charge of a stable compound is always equal to zero (meaning no charge).

For example, the

H

2

O

molecule exists as a neutrally charged substance.

(2) If the substance is an ion (either there is a positive or negative charge) the total oxidation state of the ion is the charge (i.e. oxidation state of

N

O

-1

3

ion is -1).

(3) All elements from Group 1A has an oxidation state of +1 (e.g.

N

a

+1

,

L

i

+1

). All Group 2A and 3A elements have an oxidation state of +2 and +3, respectively. (e.g.

C

a

2+

,

M

g

2+

,

A

l

3+

)

(4) Oxygen always have a charge -2 except for peroxide ion (

O

2-

2

) which has a charge of -1.

(5) Hydrogen always have a charge of +1 if it is bonded with a non-metal (as in the case of

H

C

l

) and always have a -1 charge if it is bonded with a metal (as in

A

l

H

3

).

So for your problem, according to rule 2, the overall oxidation state of

N

O

−

3

is -1.

N

O

−

3

= -1

According to rule 4, the

O

atom should have a -2 charge. But since the oxygen has a subscript in the formula, we need to multiply the charge by the subscript.

x

+ [(-2) (3)] = -1 where

x

is the oxidation state on

N

atom

solving for

x

,

x

+ (-6) = -1

x

= -1 + (+6)

x

= +5

Therefore, answer is

N

5+

x=-2

infinite number of lines, so there is an infinite number of equations.

step-by-step explanation:

there are an infinite number of line that passes through the point (-2,5)

x=-2   is one line that passes through the point

y = 5 is another line that passes through the point

(these two lines are perpendicular to each other).

since the number of   numbers are infinite and the slope is the ratio of two numbers,(change in y over change in x) we can have an infinite number of slopes.     our only condition is that it passes through the point (-2,5)

1/8 3/16 3/4

step-by-step explanation:

you put them as all the same denominator and multiply