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2 years ago

Which of the following elements has the lowest ionization energy?

Chemistry

1 answer:

larisa86 [58]2 years ago

8 0

Answer:

Explanation:

Ionization energy is defined required energy to eliminate or remove an electron from an ion or atom.

From the given elements Rb or Rubidium has the lowest ionization energy as it has lowest shielding effect, so it easy to remove electron from it's shell.

The ionization energy generally decreases from top to bottom in groups due to lower shielding effect and outer electrons are loosely packed so easy to remove and increases from left to right across a period because of valence shell stability.

Rubidium has atomic number 37 and lies below than other given elements and also placed in the left side in the periodic table.

Hence, the correct option is Rb

You might be interested in

How many moles of CH4 are in 148.6 g? Round your answer to two decimal places.

Dafna1 [17]

Answer:

9.29 mol

Explanation:

Given data:

Number of moles = ?

Mass = 148.6 g

Solution:

Number of moles = mass/ molar mass

Molar mass of CH₄ = 16 g/mol

Now we will put the values in formula.

Number of moles = 148.6 g/ 16 g/mol

Number of moles = 9.29 mol

Thus 148.6 g have 9.29 moles.

6 0

2 years ago

In an ionic compound, the size of the ions affects the internuclear distance (the distance between the centers of adjacent ions)

jeyben [28]

Answer:

Li2S> Na2S> K2S> CsS

Explanation:

The lattice energy of ionic species depends on the relative sizes of ions in the ionic compounds. As the size of ions increases, the lattice energy decreases and vice versa.

When the size of the anions are the same, the lattice energy now depends on the relative sizes of the cations. Therefore, since all the compounds are sulphides and the order of magnitude of ionic sizes is: Li^+ < Na^+ < K^+ < Cs^+.

Therefore, the order of decrease in lattice energy is; Li2S> Na2S> K2S> CsS

7 0

2 years ago

Radio stations identify themselves by their position on the radio dial such as 90.1 and 93.3. This number is based on the number

netineya [11]

D. frequency is the answer

4 0

3 years ago

A sample of food containing 27 g of fat, 48 g of carbohydrates and 20 g of protein is burned in a bomb calorimeter. In a perfect

rosijanka [135]

Answer:

38.3958 °C

Explanation:

As,

1 gram of carbohydrates on burning gives 4 kilocalories of energy

1 gram of protein on burning gives 4 kilocalories of energy

1 gram of fat on burning gives 9 kilocalories of energy

Thus,

27 g of fat on burning gives 9*27 = 243 kilocalories of energy

20 g of protein on burning gives 4*20 = 80 kilocalories of energy

48 gram of carbohydrates on burning gives 4*48 = 192 kilocalories of energy

Total energy = 515 kilocalories

Using,

$Q=m_{water}\times C_{water}\times (T_f-T_i)$

Given: Volume of water = 23 L = 23×10⁻³ m³

$Density=\frac{Mass}{Volume}$

Density of water= 1000 kg/m³

So, mass of the water:

$Mass\ of\ water=Density \times {Volume\ of\ water}$

$Mass\ of\ water=1000 kg/m^3 \times {0.023\ m^3}$

Mass of water = 23 kg

Initial temperature = 16°C

Specific heat of water = 0.9998 kcal/kg°C

$515=23\times 0.9998\times (T_f-16)$

Solving for final temperature as:

Final temperature = 38.3958 °C

8 0

2 years ago

g Calculate the pOH of a solution that results from mixing 23.3 mL of 0.16 M trimethylamine ((CH3)3N) with 44.1 mL of 0.15 M (CH

hichkok12 [17]

Answer:

pOH = 5.961

Explanation:

To find the pH of a weak base we can use Henderson-Hasselbalch equation for weak bases:

pOH = pKb + log [(CH₃)₃NHCl] / [(CH₃)₃N]

Where pKb is -log Kb = 4.187 and [] could be taken as moles of each specie.

Moles (CH₃)₃NHCl:

0.0441L * (0.15mol/L) = 6.615x10⁻³moles

Moles (CH₃)₃N:

0.0233L * (0.16mol/L) = 3.728x10⁻³moles

And pOH is:

pOH = pKb + log [(CH₃)₃NHCl] / [(CH₃)₃N]

pOH = 4.187 + log [6.615x10⁻³moles] / [3.728x10⁻³moles]

6 0

2 years ago