Write the chemical symbol for an element in Period 6 and Group 2A

Which is a way that biotechnology has Not helped society?

Trava [24]

New, stronger bacteria have evolved that are resistant to antibiotics.

3 0

3 years ago

Read 2 more answers

Mass has to do with how many particles

Ganezh [65]

The law of definite proportions agrees with Dalton atomic theory.

What is Dalton atomic theory?

It state that all matters is made of very tiny particles called atom. atoms are individual particles which can not be created or be destroyed in a chemical reactions. Atoms of given elements are identical in mass and chemical properties. Atoms of

different elements have different masses and chemical properties.

The law of definite proportions also known as proust's law ,state that a chemical compound contain the same proportion of elements by mass.this law is one of the stoichiometry .

Thus ,

This is the reason why it is agrees with dalton atomic theory.

To know more about Dalton atomic theory click-

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6 0

1 year ago

Explain why the electron configuration of 2-3-1 represents an atom in an excited state.

Allushta [10]

Answer:

The excited state electron configuration of an atom indicates the promotion of a valence electron to a higher energy state.

4 0

3 years ago

Find the % of H in ammonium hydroxide (NH4OH)

nikklg [1K]

Total number of atoms = 7

Total number of H atom = 5

% of H in ammonium hydroxide = 5/7 ×100 = 71.4 %

3 0

2 years ago

The question is in the picture below

Rus_ich [418]

Answer:

$\Delta\text{H}_1+2\Delta\text{H}_2-\Delta\text{H}_3$

Explanation:

Hess's Law of Constant Heat Summation states that if a chemical equation can be written as the sum of several other chemical equations, the enthalpy change of the first chemical equation is equal to the sum of the enthalpy changes of the other chemical equations. Thus, the reaction that involves the conversion of reactant A to B, for example, has the same enthalpy change even if you convert A to C, before converting it to B. Regardless of how many steps it takes for the reactant to be converted to the product, the enthalpy change of the overall reaction is constant.

With Hess's Law in mind, let's see how A can be converted to 2C +E.

$\bf{\text{A} \rightarrow 2\text{B}}$ (Δ $\text{H}_1$ ) -----(1)

Since we have 2B, multiply the whole of II. by 2:

$\bf{2\text{B} \rightarrow 2\text{C} +2\text{D}}$ (2Δ $\text{H}_2$ ) -----(2)

This step converts all the B intermediates to 2C +2D. This means that the overall reaction at this stage is $\text{A} \rightarrow 2\text{C} +2\text{D}$ .

Reversing III. gives us a negative enthalpy change as such:

$\bf{2\text{D} \rightarrow \text{E}}$ (-Δ $\text{H}_3$ ) -----(3)

This step converts all the D intermediates formed from step (2) to E. This results in the overall equation of $\text{A} \rightarrow 2\text{C} +\text{E}$ , which is also the equation of interest.

Adding all three together:

$\text{A} \rightarrow 2\text{C}+\text{E}$ ( $\bf{\Delta\text{H}_1+2\Delta\text{H}_2-\Delta\text{H}_3 }$ )

Thus, the first option is the correct answer.

Supplementary:

To learn more about Hess's Law, do check out: brainly.com/question/26491956

4 0

1 year ago