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3 years ago

PLEASE HELP!!

Chemistry

2 answers:

Alex17521 [72]3 years ago

6 0

Answer:

Rb is an alkali metal.

Explanation:

The elements characterized by having a single electron in its outermost orbital (s) are called alkali metals or simply alkaline metals.

Due to the presence of this electron, they are chemically very reactive because they have a tendency to lose this electron. In other words, their high reactivity is due to the fact that they form chemical bonds with many types of substances and elements and do so easily. This is due to its high electronegativity.

Like all metals, they are very good thermal and electrical conductors. But in comparison, alkali metals are soft and have a low melting point due to their metallic bond. This link is quite weak because it is the external electrons that are responsible for the bond and in these metals there is only one electron per atom.

The alkali metals are located in group 1 of the periodic table and are: lithium (Li), sodium(Na), potassium(K), rubidium(Rb), cesium(Cs) and francium(Fr).

Musya8 [376]3 years ago

4 0

Rubidium is a alkali metal.

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A solution is 5.00% potassium chloride by mass. How much potassium chloride would you expect to collect by evaporating 150.0 g o

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Answer:

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Explanation:

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Which of the following reactions is possible according to Dalton's atomic theory? View Available Hint(s) Which of the following

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4 years ago

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4 years ago

Read 2 more answers

How many grams C3H7OH can be made by reacting with 7.3L of CO2 at STP

Komok [63]

Answer:

6.54g of C3H7OH

Explanation:

Step 1:

Determination of the number of mole of CO2 that occupy 7.3L at stp.

This can be obtained as follow:

1 mole of a gas occupy 22.4L at stp.

Therefore, Xmol of CO2 will occupy 7.3L at stp i.e

Xmol of CO2 = 7.3/22.4

Xmol of CO2 = 0.326 mole.

Therefore, 0.326 mole of CO2 was used in the reaction.

Step 2:

The balanced equation for the reaction. This is given below:

6CO2 + 8H2O —> 2C3H7OH + 9O2

Step 3:

Determination of the number of mole of C3H7OH produced from the reaction. This is illustrated below:

From the balanced equation above,

6 moles of CO2 reacted to produce 2 moles of C3H7OH.

Therefore, 0.326 mole of CO2 will react to produce = (0.326 x 2)/6 = 0.109 mole of C3H7OH.

Step 4:

Conversion of 0.109 mole of C3H7OH to grams. This is illustrated below:

Number of mole of C3H7OH = 0.109 mole.

Molar mass of C3H7OH = (12x3)+ (7x1) + 16 + 1 = 60g/mol

Mass of C3H7OH =..?

Mass = mole x molar mass

Mass of C3H7OH = 0.109 x 60

Mass of C3H7OH = 6.54g.

Therefore, 6.54g of C3H7OH is produced from the reaction.

5 0

3 years ago