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2 years ago

Each element is defined by the number of

Chemistry

2 answers:

Nastasia [14]2 years ago

6 0

Each number is defined by the number of protons.

pentagon [3]2 years ago

4 0

Answer:

The atomic number of an element is equal to the number of protons in each atom and defines the element. For example, all carbon atoms contain 6 protons in their atomic nucleus; so the atomic number of carbon is 6.

What does the number of an element represent?

The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of every atom of that element. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus.

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0=4 Balance this equation H₂sicl2+ H₂O → H8Si4O4 + HCl

zaharov [31]

Balanced Equation is

4H2SiCl2+4H2O → H8Si4O4 + 8HCl

8 0

2 years ago

Which of the statements below is not a characteristic of economically developed nations?

nikklg [1K]

I would go with option #4, reduced use of resources!

:V

6 0

3 years ago

Read 2 more answers

Ultra Clorox bleach is 6.68% sodium hypochlorite in water. How much of each is needed to make an 800.mL bottle?

sweet-ann [11.9K]

If we have 6.68% NaClO, it is the same as saying--> 6.68 grams NaClO= 100 mL of solution. we can use this as a conversion.

800. mL (6.68 mL/ 100 mL)= 53.4 mL

solution = solute + solvent

solute= NaClO
solvent= H2O

solvent= 800-53.4= 747 mL of H2O

so, we you need 53.4 mL of NaClO and 747 mL of water or 53.4 grams of NaClO and 747 mL of water

7 0

3 years ago

How many moles of NH3 can be produced from 30.0 mol of H2 and excess N2?

VMariaS [17]

20 mol of NH, can be produce from 30 mol o H2

6 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]

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

Explanation:

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

Each element is defined by the number of​

Each element is defined by the number of