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2 years ago

Why is helium less reactive than hydrogen?

Chemistry

1 answer:

algol132 years ago

6 0

Answer:

Each helium atom has a full valence electron shell, but each hydrogen atom only has one valence electron.

Explanation:

Atoms are made of protons, neutrons and electrons. Protons and neutrons are in the nucleus and electrons orbit in energy levels. Chemical properties of elements depend mostly on the number of electrons in the valence / outermost energy shell.

Elements that have an incomplete energy shell are more reactive as they try to gain a complete outer shell electron configuration either by losing electrons or gaining electrons from the valence energy shell.

He is a noble gas, which means it has a full valence electron shell therefore it is inert. H has one electron in the outer shell therefore its reactive by gaining or losing the outermost electron.

therefore H is more reactive than He as it has an incomplete valence electron shell.

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You are given three bottles labeled a, b, and

ElenaW [278]

Answer :Solid in bottle a is ionic, solid in bottle b is molecular and solid in bottle c is ionic.

Explanation :

Ionic compound is formed when a metal atom donates one or more electrons to a non metal. This results in the formation of a cation ( a positive ion) and an anion ( a negative ion). These ions are bonded to each other by electrostatic attraction.

The intermolecular forces in case of a an ionic compound are very strong.

The melting point of a substance depends on how strongly the molecules are attracted to each other. Stronger the forces, higher is the melting point.

Therefore ionic compounds always have very high melting points.

On the other hand, covalent compounds have weak intermolecular forces. Therefore they have low melting points.

Based on above discussion, we can classify the given compounds as follows.

a) Solid in bottle a is Ionic as it has high melting point.

b) Solid in bottle b is molecular as it has low melting point.

c) Solid in bottle c is Ionic as it has high melting point.

6 0

2 years ago

What is the maximum volume of a 0.788 M CaCl2 solution that can be prepared using 85.3 g CaCl2?

Anna11 [10]

Molar mass CaCl₂ = 110.98 g/mol

Number of moles:

1 mole CaCl₂ ---------> 110.98 g
n mole CaCl2 ---------> 85.3 g

n = 85.3 / 110.98

n = 0.7686 moles of CaCl₂

Volume = ?

M = n / V

0.788 = 0.7686 / V

V = 0.7686 / 0.788

V = 0.975 L

hope this helps!

5 0

2 years ago

In a chemical reaction that takes place at a fixed pressure and volume, the enthalpy change (ΔH) is –585 kJ/mol. Will this react

Molodets [167]

by sign convention Δ $H$ is negative it means an exothermic reaction where the heat is lose so the temperature decreases.

5 0

2 years ago

Read 2 more answers

Which milligram quantity contains a total of four significant figures

denis23 [38]

D has a total of four significant figures.

7 0

2 years ago

Read 2 more answers

BH+ClO4- is a salt formed from the base B (Kb = 1.00e-4) and perchloric acid. It dissociates into BH+, a weak acid, and ClO4-, w

Len [333]

Answer:

The pH of 0.1 M BH⁺ClO₄⁻ solution is 5.44

Explanation:

Given: The base dissociation constant: $K_{b}$ = 1 × 10⁻⁴, Concentration of salt: BH⁺ClO₄⁻ = 0.1 M

Also, water dissociation constant: $K_{w}$ = 1 × 10⁻¹⁴

The acid dissociation constant ( $K_{a}$ ) for the weak acid (BH⁺) can be calculated by the equation:

$K_{a}. K_{b} = K_{w}$

$\Rightarrow K_{a} = \frac{K_{w}}{K_{b}}$

$\Rightarrow K_{a} = \frac{1\times 10^{-14}}{1\times 10^{-4}} = 1\times 10^{-10}$

Now, the acid dissociation reaction for the weak acid (BH⁺) and the initial concentration and concentration at equilibrium is given as:

Reaction involved: BH⁺ + H₂O ⇌ B + H₃O+

Initial: 0.1 M x x

Change: -x +x +x

Equilibrium: 0.1 - x x x

The acid dissociation constant: $K_{a} = \frac{\left [B \right ] \left [H_{3}O^{+}\right ]}{\left [BH^{+} \right ]} = \frac{(x)(x)}{(0.1 - x)} = \frac{x^{2}}{0.1 - x}$