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3 years ago

What is the right answer

Chemistry

2 answers:

ArbitrLikvidat [17]3 years ago

5 0

Answer:The answer is D

Explanation:

Scrat [10]3 years ago

3 0

Answer:

im pretty sure its D

Explanation:

The seasons result from the tilt of the earth on its axis

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In the bronsted-lowry acid-base definition, an acid is a molecule (or ion) that _____ a proton and a base is a molecule (or ion)

agasfer [191]

In the Bronsted-Lowry acid-base definition, an acid is a molecule (or ion) that donates a proton and a base is a molecule (or ion) that accepts a proton.

Bronsted-Lowry theory of acid and bases took the Arrhenius definition one step further, as a substance no longer needed to be composed of hydrogen (H+) or hydroxide (OH-) ions in order to be classified as an acid or base. For example , consider the following chemical equation:

HCl (aq) +NH₃ (aq) → NH⁺₄ (aq) + Cl⁻(aq)

Here, hydrochloric acid (HCl) "donates" a proton (H+) to ammonia (NH3) which "accepts" it , forming a positively charged ammonium ion (NH4⁺) and a negatively charged chloride ion (Cl⁻). Therefore, HCl is a Bronsted-Lowry acid (donates a proton) while the ammonia is a Bronsted-Lowry base (accepts a proton). Also, Cl⁻ is called the conjugate base of the acid HCl and NH4⁺ is called the conjugate acid of the base NH3.

A Bronsted-Lowry acid is a proton (hydrogen ion) donor.

A Bronsted-Lowry base is a proton (hydrogen ion) acceptor.

In this theory, an acid is a substance that can release a proton (like in the Arrhenius theory) and a base is a substance that can accept a proton.

Learn more about Bronsted-Lowry theory here : brainly.com/question/12983200

#SPJ4

3 0

2 years ago

How many liters of water vapor can be produced if 8.9 liters of methane gas (CH4) are combusted, if all measurements are taken a

Delvig [45]

We know, mole of gas in ideal conditions is 22.414 L
Here, CH4 volume = 8.9L

So, number of moles = 8.9 / 22.414 = 0.397 moles
Here, in balanced equation we have a ratio CH4 : H2O = 1:2.

So, mole so water = , 0.397*2= 0.794 moles
In liters it would be: 0.794 * 22.414 = 17.80 L

In short, Your Answer would be 17.80 Liters

Hope this helps!

8 0

3 years ago

Which of the following is not included in John Dalton's modern theory of the atom?

Akimi4 [234]

The answer for the following question is option "C".

Option C is not included in the John Dalton's modern theory of an atom.

"It states atoms of different elements combine to form new compound" but not new elements

Explanation:

According to John's Dalton's modern theory of an atom:

1. All matter is composed of atoms.

2. Atoms cannot be created,destroyed or subdivided in the ordinary chemical reactions.

3. Atoms of one element differ in the properties from atoms of an another element.

(i.e.)Each and every atom of the element has its own unique properties of their own.

4. Atoms of one element combine with the atoms of another element to form new compound.

5. Atoms that make up an element are identical to each other.

7 0

3 years ago

In most of its ionic compounds, cobalt is either Co(II) or Co(III). One such compound, containing chloride ion and waters of hyd

Elina [12.6K]

Answer: The mass percent of $Co^{3+},Cl^{-},H^+\text{ and }O^{2-}$ ions in the compound are 49.28 %, 29.79 %, 2.33 % and 18.63 % respectively

Explanation:

We are given:

Mass of silver chloride = 0.308 grams

Mass of cobalt (III) oxide = 0.145 grams

Mass of sample containing chloride ions = 0.256 grams

Mass of sample containing $Co^{3+}$ ions = 0.416 grams

We know that:

Molar mass of silver chloride = 143.4 g/mol

Molar mass of chlorine ion = 35.45 g/mol

Molar mass of cobalt (III) oxide = 165.86 g/mol

Molar mass of $Co^{3+}$ ion = 117.86 g/mol

Molar mass of water = 18 g/mol

Molar mass of hydrogen ion = 1 g/mol

Molar mass of oxygen ion = 16 g/mol

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ ......(1)

To calculate the mass percentage of ions in sample, we use the equation:

$\text{Mass of ion}}{\text{Mass of sample}}\times 100$ .......(2)

For chlorine ion:

Calculating moles of AgCl by using equation 1:

Moles of AgCl = $\frac{0.308g}{143.4g/mol}=0.00215mol$

The chemical equation for the ionization of silver chloride follows:

$AgCl\rightarrow Ag^++Cl^-$

By Stoichiometry of the reaction:

1 mole of silver chloride produces 1 mole of chlorine ions

So, 0.00215 moles of silver chloride will produce = $\frac{1}{1}\times 0.00215=0.00215mol$ of chloride ions

Mass of chloride ions = $(0.00215mol\times 35.45g/mol)=0.0762g$

Putting values in equation 2, we get:

$\text{Mass percent of chloride ion}=\frac{0.0762g}{0.256g}\times 100\\\\\text{Mass percent of chloride ion}=29.76\%$

Mass percent of chloride ion = 29.76 %

For $Co^{3+}$ ion:

Calculating moles of cobalt (III) oxide by using equation 1:

Moles of cobalt (III) oxide = $\frac{0.145g}{165.86g/mol}=0.00087mol$

The chemical equation for the ionization of cobalt (III) oxide follows:

$Co_2O_3\rightarrow 2Co^{3+}+3O^{2-}$

By Stoichiometry of the reaction:

1 mole of cobalt (III) oxide produces 2 moles of cobalt ions

So, 0.00087 moles of cobalt (III) oxide will produce = $\frac{2}{1}\times 0.00087=0.00174mol$ of cobalt ions

Mass of cobalt ions = $(0.00174mol\times 117.86g/mol)=0.205g$

Putting values in equation 2, we get:

$\text{Mass percent of cobalt ion}=\frac{0.205g}{0.416g}\times 100\\\\\text{Mass percent of cobalt ion}=49.28\%$

Mass percent of cobalt ion = 49.28 %

For hydrogen and oxygen ion:

Calculating mass percent of water:

Mass percent of water = 100 - (29.76 + 49.28) = 20.96 %

Let the mass of compound be 100 grams. So, mass of water in the compound will be 20.96 g

For hydrogen:

In 18 grams of water, mass of hydrogen ion present is (1 × 2) = 2 g

So, in 20.96 grams of water, mass of hydrogen ion present will be = $\frac{2}{18}\times 20.96=2.33g$

Putting values in equation 2, we get:

$\text{Mass percent of hydrogen ion}=\frac{2.33g}{100g}\times 100\\\\\text{Mass percent of hydrogen ion}=2.33\%$

Mass percent of hydrogen ion = 2.33 %

For oxygen:

In 18 grams of water, mass of oxygen ion present is (16 × 1) = 16 g

So, in 20.96 grams of water, mass of oxygen ion present will be = $\frac{16}{18}\times 20.96=18.63g$

Putting values in equation 2, we get:

$\text{Mass percent of oxygen ion}=\frac{18.63g}{100g}\times 100\\\\\text{Mass percent of oxygen ion}=18.63\%$

Mass percent of oxygen ion = 18.63 %

Hence, the mass percent of $Co^{3+},Cl^{-},H^+\text{ and }O^{2-}$ ions in the compound are 49.28 %, 29.79 %, 2.33 % and 18.63 % respectively

7 0

3 years ago

can someone explain how this is wrong? I don’t think it is wrong but my chem teacher deducted points. so why?

ruslelena [56]

Answer: measure the mass (48.425g) of KCl

Explanation:

To prepare the solution 0.65M KCl we must measure the mass of KCl that would be dissolved in 1L of the solution. This can be achieved by:

Molar Mass of KCl = 39 + 35.5 = 74.5g/mol

Number of mole (n) = 0.65

Mass conc of KCl = n x molar Mass

Mass conc of KCl = 0.65 x 74.5 = 48.425g

Therefore, to make 0.65M KCl, we must measure 48.425g

7 0

3 years ago