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3 years ago

How are parentheses used in chemical formulas

2 answers:

8 0

In a chemical compound, parenthesis are used to distinguish the number of polyatomic ions from the number of atoms. Such as in the compound calcium nitrate, it is written as $Ca(NO_{3} ) _{2}$ . This means there are two nitrate ions for every one calcium ion.

Zarrin [17]3 years ago

3 0

it is meant to distinguish the number of polyatomic ions from the number of atoms in a given polyatomic ion. an example is Ca(NO3)2

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3 years ago

Can there be displacement of an object in the absence of any force acting on it? Think, Discuss it with your friends and teacher

Fudgin [204]

Answer:

An object can have a displacement in the absence of any external force acting on it

Explanation:

When a object moves with a constant velocity (v), then it gets displaced in the direction of motion but the net external force experienced by the object is zero.

F external =ma

If object moves with constant velocity, acceleration is zero.

Since, a=0 ⟹F external =0

Using s=ut+ 1/2 at ^2

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Hence, an object can have a displacement in the absence of any external force acting on it

Hope this helped you:)

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3 years ago

A 500 W hair dyer is used to dry hair for 6 minutes a day for 3 days. How much energy is used? A laptop uses 75 W. The cot of el

zzz [600]

Answer:

See the answers below.

Explanation:

We will solve this problem by calculating each part separately.

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$500 [W]*[\frac{6min}{1day} ]*[\frac{1day}{24hr} ]*[\frac{1hr}{60min} ]=2.083 [W]$

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Therefore.

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3 years ago

How does lemon produce electricity

oksian1 [2.3K]

Answer:

Below!

Explanation:

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2 years ago