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3 years ago

Pls help and i will mark brainliest

Chemistry

2 answers:

myrzilka [38]3 years ago

6 0

Answer:

No. 3 lithium

Explain that lithium has 3 protons and 3 electrons. There are 2 electrons on the first energy level and 1 electron on the second

No. 4 Hydrogen (H) and helium (He) have a valence shell containing one and two electrons respectively. They make up the first period (row) of the periodic table. Their valence electron/s are in the first energy level (n=1) , as is denoted by 1s1 and 1s2 .

That's all i dont know if this is right though. 

Serjik [45]3 years ago

5 0

Sodium
Beryllium
Lithium
Helium
Potassium
Fluorine

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What is Alkali metals

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Answer:

The alkali metals consist of the chemical elements lithium, sodium, potassium, rubidium, caesium, and francium. Together with hydrogen, they constitute group 1, which lies in the s-block of the periodic table

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If one gram of sulphur dioxide contains x molecules what will be the number of molecules in 1g of methane

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The ratio of molecules in sulphur dioxide and methane will be the same as the ratio of their moles. So, first of all we should find out the number of moles of sulphur dioxide in 1 gram of sulphur dioxide in 1 gram of sulphur dioxide, and the number of moles of methane in 1 gram of methane. This can be done as follows :

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$\frac{1}{64}$ mole of methane contains = x molecules

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2 years ago

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