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3 years ago

How many groups and periods are present in the periodic table?

Chemistry

2 answers:

PilotLPTM [1.2K]3 years ago

7 0

Answer:

Explanation:

There are seven periods in the periodic table, with each one beginning at the far left. A new period begins when a new principal energy level begins filling with electrons. Period 1 has only two elements (hydrogen and helium), while periods 2 and 3 have 8 elements. Periods 4 and 5 have 18 elements.

Elenna [48]3 years ago

6 0

Answer:

<h2>18 groups</h2>

In the periodic table, there are 7 periods and 18 groups.

Explanation:

#CARRY ON LEARNING

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Explanation:

We are given:

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According to mole concept:

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We know that:

Charge on 1 electron = $1.6\times 10^{-19}C$

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To calculate the time required, we use the equation:

$I=\frac{q}{t}$

where,

I = current passed = 40.0 A

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t = time required = ?

Putting values in above equation, we get:

$40.0=\frac{42551181 C}{t}\\\\t=1063779sec$

Converting this into hours, we use the conversion factor:

1 hr = 3600 seconds

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worty [1.4K]

Answer:

29260J

Explanation:

Given parameters:

Mass of water sample = 100g

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Unknown:

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Solution:

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3 years ago

How many groups and periods are present in the periodic table?​

How many groups and periods are present in the periodic table?