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igomit [66]
3 years ago
11

HELP ME

Chemistry
1 answer:
krok68 [10]3 years ago
3 0

Answer:

D group

................

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What is the formula (with cation and anion charges) for copper (II) hydroxide? ​
Thepotemich [5.8K]

Answer:

Cu²⁺(OH)⁻₂

Explanation:

Step 1: Find the symbols for the substances

For copper, see your periodic table. Copper is "Cu".

For hydroxide, see your polyatomic ions chart. Hydroxide is "OH".

Step 2: Find the charges for each element.

Copper (II)'s charge is 2, which is the roman numerals in the brackets.

Hydroxide's charge is -1.

Charges are written as superscripts. You do not need to write "1".

In formulas, write the positively charged atom first.

Cu²⁺(OH)⁻   Put brackets around hydroxide because it has 2 elements.

Step 3: Write the number of atoms.

The number of atoms that an element has is the same as its partner's charge.

The charge of copper is 2, so hydroxide has 2 atoms.

The charge of hydroxide is 1, so copper has 1 atom.

Cu²⁺₁(OH)⁻₂

You do not need to write the "1" for atoms.

Cu²⁺(OH)⁻₂

8 0
3 years ago
What percentage of atoms in the entire universe are hydrogen atoms?
lisabon 2012 [21]
The percentage of atoms in the universe that are hydrogen are 90%
3 0
3 years ago
Which occurs whenever valence electrons are shared or transferred between atoms?
Tanzania [10]

Whenever electrons are shared or transferred between atoms there is a chemical reaction.

The electrons that are being transferred between atoms (two or more) create new bonds, which enable the production of a new substance. This process is then known as a chemical reaction.

4 0
3 years ago
Calculate the standard enthalpy change for the reaction at 25 ∘ 25 ∘ C. Standard enthalpy of formation values can be found in th
WINSTONCH [101]

<u>Answer:</u> The standard enthalpy change of the reaction is coming out to be -16.3 kJ

<u>Explanation:</u>

Enthalpy change is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles. It is represented as \Delta H

The equation used to calculate enthalpy change is of a reaction is:  

\Delta H_{rxn}=\sum [n\times \Delta H_f(product)]-\sum [n\times \Delta H_f(reactant)]

For the given chemical reaction:

Mg(OH)_2(s)+2HCl(g)\rightarrow MgCl_2(s)+2H_2O(g)

The equation for the enthalpy change of the above reaction is:

\Delta H_{rxn}=[(1\times \Delta H_f_{(MgCl_2(s))})+(2\times \Delta H_f_{(H_2O(g))})]-[(1\times \Delta H_f_{(Mg(OH)_2(s))})+(2\times \Delta H_f_{(HCl(g))})]

We are given:

\Delta H_f_{(Mg(OH)_2(s))}=-924.5kJ/mol\\\Delta H_f_{(HCl(g))}=-92.30kJ/mol\\\Delta H_f_{(MgCl_2(s))}=-641.8kJ/mol\\\Delta H_f_{(H_2O(g))}=-241.8kJ/mol

Putting values in above equation, we get:

\Delta H_{rxn}=[(1\times (-641.8))+(2\times (-241.8))]-[(1\times (-924.5))+(2\times (-92.30))]\\\\\Delta H_{rxn}=-16.3kJ

Hence, the standard enthalpy change of the reaction is coming out to be -16.3 kJ

6 0
3 years ago
The terms Q and K refer to reaction components at non-equilibrium and equilibrium conditions, respectively. For a forward reacti
daser333 [38]

Answer:

The value of Q must be less than that of K.

Explanation:

The difference of K and Q can be understood with the help of an example as follows

         A ⇄ B

In this reaction A is converted into B but after some A is converted , forward reaction stops At this point , let equilibrium concentration of B be [B] and let equilibrium concentration of A be [A]

In this case ratio of  [B] and  [A]  that is

K =  [B] / [A] which is called equilibrium constant.

But if we measure the concentration of A and B ,before equilibrium is reached , then the ratio of the concentration of A and B will be called Q. As reaction continues concentration of A increases and concentration of B decreases. Hence Q tends to be equal to K.

Q = [B] / [A] . It is clear that Q < K before equilibrium.

If Q < K , reaction will proceed towards equilibrium or forward reaction will

proceed .

8 0
3 years ago
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