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3 years ago

Francium is the most reactive element in Group 1.

Chemistry

2 answers:

natali 33 [55]3 years ago

6 0

Answer:

Francium is hypothesized to be the most reactive metal, but so little of it exists or can be synthesized, and the longest half-life of its most abundant isotope is 22.00 minutes, so that its reactivity cannot be determined experimentally.

Explanation:

Francium is an alkali metal in group 1/IA. All alkali metals have one valence electron. As you go down the group, the number of electron energy levels increases – lithium has two, sodium has three, etc..., as indicated by the period number. The result is that the outermost electron gets further from the nucleus. The attraction from the positive nucleus to the negative electron is less. This makes it easier to remove the electron and makes the atom more reactive.

Experimentally speaking, cesium (caesium) is the most reactive metal.

Alika [10]3 years ago

6 0

Answer:

Explanation:

all group 1 elements have 1 electron in their outer shell,making this the electron that is involved in reactions.as you move down a group in The periodic table the number of shells increases,which means that the outer electron is further from the nucleus.as there are now more shells between the electron and the nucleus,the outer electron experiences more shielding and therefore less attraction to the nucleus. This means that the outer electron is more easily removed in francium than other group one element

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6) A student measures out 96.21 g of sulfur for an experiment. How many moles of Sulfur are in this

barxatty [35]

Atomic mass of Sulfur = 32g

32g of Sulfur is one mole.

1g of Sulfur is $\frac{1}{32} moles$

96.21g of Sulfur is $\frac{96.21}{32} moles=> 3moles(appx)$

5 0

3 years ago

Read 2 more answers

What did scientists discover when they arranged elements in order of increasing atomic mass?

asambeis [7]

The scientists discovered that when they organized elements in order of increasing atomic mass there is a pattern of repetition of properties (A). The periodic law was developed by Dmitri Mendeleev and Lothar Mayer in 1869. They worked independently of each other and both created a periodic table. They both arranged the items on the table by weight and both suggested that certain properties of the elements recur. The Mendeleev table is the most important table because the values for the atomic mass are the most accurate.

4 0

2 years ago

How much heat is absorbed when a 298.3 g piece of brass goes from 30.0 to 150

igor_vitrenko [27]

Answer:

Q = 1360.248 j

Explanation:

Given data:

Mass of brass = 298.3 g

Initial temperature = 30.0°C

Final temperature = 150°C

Specific heat capacity of brass = 0.038 J/g.°C

Heat absorbed = ?

SOLUTION:

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = 150°C - 30.0°C

ΔT = 120°C

Q = 298.3 g × 0.038 J/g.°C × 120°C

Q = 1360.248 j

3 0

3 years ago

1.15.7 cm3 of HCl completely neutralised 25 cm3 of LiOH. The HCl was 2 mol/dm3.The equation is :

Whitepunk [10]

Answer:

C₂ = 1.26 mol/dm³

Explanation:

Given data:

Volume of HCl =V₁ = 15.7 cm³

Volume of LiOH = V₂ = 25 cm³

Concentration of HCl =C₁ = 2 mol/dm³

Concentration of LiOH =C₂= ?

Solution:

Chemical equation:

LiOH + HCl → LiCl + H₂O

Formula:

C₁V₁ = C₂V₂

by putting values,

15.7 cm₃× 2 mol/dm³ = C₂× 25 cm³

C₂ = 15.7 cm₃× 2 mol/dm³ / 25 cm³

C₂ = 31.4 cm₃.mol/dm³ / 25 cm³

C₂ = 1.26 mol/dm³

8 0

2 years ago

Phosphine, an extremely poisonous and highly reactive gas, will react with oxygen to form tetraphosphorus decoxide and water, as

erica [24]

Answer: The amount of $P_4O_{10}$ formed is 469.8 grams.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ ......(1)

Given mass of phosphine = 225 g

Molar mass of phosphine = 34 g/mol

Putting values in equation 1, we get:

$\text{Moles of phosphine}=\frac{225g}{34g/mol}=6.62mol$

The given chemical reaction follows:

$4PH_3(g)+8O_2(g)\rightarrow P_4O_{10}(s)+6H_2O(g)$

Assuming that oxygen gas is present in excess, it is considered as an excess reagent.

Phosphine is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

4 moles of phosphine produces 1 mole of $P_4O_{10}$

So, 6.62 moles of phosphine will produce = $\frac{1}{4}\times 6.62=1.655mol$ of $P_4O_{10}$

Now, calculating the mass of $P_4O_{10}$ by using equation 1:

Molar mass of $P_4O_{10}$ = 283.9 g/mol

Moles of $P_4O_{10}$ = 1.655 moles

Putting values in equation 1, we get:

$1.655mol=\frac{\text{Mass of }P_4O_{10}}{283.9g/mol}\\\\\text{Mass of }P_4O_{10}=(1.655mol\times 283.9g/mol)=469.8g$

Hence, the amount of $P_4O_{10}$ formed is 469.8 grams.

8 0

2 years ago