All categories

3 years ago

Which element is classified as an alkali metal?

2 answers:

4 0

The alkali metals are a group (column) in the periodic table consisting of the chemical elements lithium (Li), sodium (Na), potassium (K), [note 1] rubidium (Rb), caesium (Cs), [note 2] and francium (Fr).

dusya [7]3 years ago

3 0

Explanation:

All the elements of group 1 in the periodic table are known as alkali metals. These are lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (fr).

Characteristics of alkali metals are as follows.

Alkali metals are soft and can be cut with a knife.
They are good conductors of heat and electricity.
They have only 1 electron in their outermost sub-shell.
They are very reactive.
Alkali metals are ionic in nature.

You might be interested in

Calculate the solubility of hydrogen in water at an atmospheric pressure of 0.380 atm (a typical value at high altitude).

Pani-rosa [81]

The question is incomplete, here is the complete question:

Calculate the solubility of hydrogen in water at an atmospheric pressure of 0.380 atm (a typical value at high altitude).

Atmospheric Gas Mole Fraction kH mol/(L*atm)

$N_2$ $7.81\times 10^{-1}$ $6.70\times 10^{-4}$

$O_2$ $2.10\times 10^{-1}$ $1.30\times 10^{-3}$

Ar $9.34\times 10^{-3}$ $1.40\times 10^{-3}$

$CO_2$ $3.33\times 10^{-4}$ $3.50\times 10^{-2}$

$CH_4$ $2.00\times 10^{-6}$ $1.40\times 10^{-3}$

$H_2$ $5.00\times 10^{-7}$ $7.80\times 10^{-4}$

Answer: The solubility of hydrogen gas in water at given atmospheric pressure is $1.48\times 10^{-10}M$

Explanation:

To calculate the partial pressure of hydrogen gas, we use the equation given by Raoult's law, which is:

$p_{\text{hydrogen gas}}=p_T\times \chi_{\text{hydrogen gas}}$

where,

$p_A$ = partial pressure of hydrogen gas = ?

$p_T$ = total pressure = 0.380 atm

$\chi_A$ = mole fraction of hydrogen gas = $5.00\times 10^{-7}$

Putting values in above equation, we get:

$p_{\text{hydrogen gas}}=0.380\times 5.00\times 10^{-7}\\\\p_{\text{hydrogen gas}}=1.9\times 10^{-7}atm$

To calculate the molar solubility, we use the equation given by Henry's law, which is:

$C_{H_2}=K_H\times p_{H_2}$

where,

$K_H$ = Henry's constant = $7.80\times 10^{-4}mol/L.atm$

$p_{H_2}$ = partial pressure of hydrogen gas = $1.9\times 10^{-7}atm$

Putting values in above equation, we get:

$C_{H_2}=7.80\times 10^{-4}mol/L.atm\times 1.9\times 10^{-7}atm\\\\C_{CO_2}=1.48\times 10^{-10}M$

Hence, the solubility of hydrogen gas in water at given atmospheric pressure is $1.48\times 10^{-10}M$

4 0

3 years ago

When hydrogen chloride (HCI) reacts with ammonia (NH3), ammonium chloride (NH4CI) is

givi [52]

Answer:

AMEN NNNNNNNNNNNNNNNNNNNNNNNN

6 0

3 years ago

Hi! I'm on the last question of my homework and I'm stuck on it and was wondering if anyone could help me

Semmy [17]

I am not sure but this is what I think

This question uses the formula connecting mass, density and volume
Which is Density= Mass/Volume

Convert the mass in g
92.5 kg = 92,500g

7.87g/ml = 92,500/ Volume
Volume= 92,500/7.87
= 11,753.5 ml

Now since we have to give the answer in liters we can just divide by 1000 and get
11.75 litres

5 0

2 years ago

Hydrogen is used as a rocket fuel because it is very light and reacts explosively and completely with oxygen. For the combustion

777dan777 [17]

Answer:

1. K<10−3

Explanation:

Equilibrium Constant is an expression which involves the concentration of the product divided by the concentration of the reactant molecules.

However the concentration of the pure liquid and pure solid is regarded as 1.

Equilibrium expression for the equation 2H2(g)+O2(g)⇌2H2O(g)

Equilibrium Constant = [H2O]^2/[H2]^2 x [O2]

Since H2O is a pure liquid, its concentration = 1

There fore;

Equilibrium Constant = 1/[H2]^2 x [O2]

This shows that the Equilibrium Constant of the equation will be less than 1 and greater than 0.

7 0

3 years ago

Molar mass of 4Fe(OH)2

lakkis [162]

Answer: The molar mass and molecular weight of 4Fe is 223.38.

3 0

2 years ago