All categories

1 year ago

Question 30

Chemistry

2 answers:

andre [41]1 year ago

7 0

Answer : The reaction will produce (B) 1.57 mole of magnesium hydroxide and (D) 3.14 mole of sodium chlorate.

Explanation :

First we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

$Mg(ClO_3)_2+2NaOH\rightarrow Mg(OH)_2+2NaClO_3$

From the balanced reaction we conclude that

As, 1 moles of $Mg(ClO_3)_2$ react with 2 mole of $NaOH$

So, 2.72 moles of $Mg(ClO_3)_2$ react with $2\times 2.72=5.44$ moles of $NaOH$

That means, in the given balanced reaction, $NaOH$ is a limiting reagent because it limits the formation of products and $Mg(ClO_3)_2$ is an excess reagent.

Now we have to calculate the moles of $Mg(OH)_2$ and $NaClO_3$ by using the moles of limiting reagent.

As, 2 moles of $NaOH$ react to give 1 mole of $Mg(OH)_2$

So, 3.14 moles of $NaOH$ react to give $\frac{3.14}{2}=1.57$ moles of $Mg(OH)_2$

And,

As, 2 moles of $NaOH$ react to give 2 mole of $NaClO_3$

So, 3.14 moles of $NaOH$ react to give 3.14 moles of $NaClO_3$

Therefore, the reaction will produce (B) 1.57 mole of magnesium hydroxide and (D) 3.14 mole of sodium chlorate.

cestrela7 [59]1 year ago

4 0

well #1 is A

and #2 is E

well i did just do this

You might be interested in

Explain why a propane torch is lit inside a hot air balloon during preflight preparations. Which gas law applies?

Olegator [25]

Propane torch is lit inside a hot air balloon during pre-flight preparation because the heat from the touch is needed to heat the cold air inside the balloon, so that the air will expand and become less dense and rise, thus providing a lift for the balloon. This is line with charle's law, which states that, the volume of a fixed mass of ideal gas is directly proportional to the absolute temperature. This law implies that, as the temperature of the air inside the balloon increase, the volume of the balloon also increases.

5 0

2 years ago

Read 2 more answers

Two students made the Lewis dot diagrams of NH3. The diagrams are as shown.

BigorU [14]

Answer : The correct option is, Only Student B

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $NH_3$

As we know that nitrogen has '5' valence electrons and hydrogen has '1' valence electron.

Therefore, the total number of valence electrons in $NH_3$ = 5 + 3(1) = 8

According to Lewis-dot structure, there are 6 number of bonding electrons and 2 number of non-bonding electrons.

The Lewis dot structure of student A is wrong because there is a coordinate bond present between the nitrogen and hydrogen is not covalent.

Thus, the correct Lewis-dot structure of $NH_3$ is shown by the student B.

4 0

1 year ago

The model below shows an atom of an element. 10 light gray and 8 dark gray balls sit at the center with 2 concentric black rings

MA_775_DIABLO [31]

Answer:

The Atomic Number of the atom of an element whose model is given is "8" that is option no. 'C' in the question.

Explanation:

An Atom comprises of 3 basic structures that are Protons, Neutrons and Electrons. The central part is the Nucleus which contains protons and neutrons having positive charge and no charge respectively. The electrons are revolving around the nucleus in electronic shells having the negative charge.

ATOMIC NUMBER:

Atomic number is the number of protons present inside the nucleus of an atom and it determines the place of that particular atom in the Periodic Table.

In the model, given in the question, the nucleus contains 2 types of balls dark gray colored and light gray colored. The key at the bottom shows the dark gray colored ball as having a positive charge and thus it represents the atomic number for the given atom of element which is EIGHT (8).

So, the atomic number for the given atom is 8 which is element OXYGEN.

9 0

2 years ago

Read 2 more answers

A quantity of 85.0 mL of 0.900 M HCl is mixed with 85.0 mL of 0.900 M KOH in a constantpressure calorimeter that has a heat capa

bogdanovich [222]

Explanation:

The given data is as follows.

$V_{1}$ = 85.0 ml, $M_{1}$ = 0.9 M

$V_{2}$ = 85.0 ml, $M_{1}$ = 0.9 M

Hence, number of moles of HCl and KOH will be the same because both the solutions have same volume and molarity.

So, No. of moles = Molarity × Volume

= $0.9 M \times 0.085 L$ (as 1 L = 1000 ml so, 85 ml = 0.085 L)

= 0.076 mol

As 1 mole gives 56.2 kJ/mol of heat of neutralization. Hence, calculate the heat of neutralization given by 0.076 moles as follows.

$56.2 kJ/mol \times 0.076 mol$

= 4.271 kJ

or, = 4271 J (as 1 kJ = 1000 J)

Therefore, heat released = - heat of gained by calorimeter

Since, it is given that density of the solution is similar to the density of water which is 1 g/ml.

Hence, mass of HCl = density × Volume of HCl

= 1.00 g/ml × 85.0 ml

= 85 g

Similarly, mass of KOH = = density × Volume of HCl

= 1.00 g/ml × 85.0 ml

= 85 g

Hence, total mass of the solution = 85 g + 85 g

= 170 g

Also, q = $mC \Delta T$

4271 J = $170 g \times 325 J/^{o}C \times (T_{f} - 18.24)^{o}C$

0.0773 = $T_{f} - 18.24$

$T_{f}$ = $18.317^{o}C$

Thus, we can conclude that final temperature of the mixed solution is $18.317^{o}C$ .

6 0

2 years ago

In two or more complete sentences explain how to balance the chemical equation and classify its reaction type. ___P4 + ___O2 ⟶ _

Serhud [2]

According to the conversation of mass, mass cannot be created or destroyed. This means whatever is done to one side, must be done to the other.

There are 4 Phosphorus atoms on the left, there must be 4 on the right. To do this, you must multiply the P2O3 by 2 to get 4 Phosphorus atoms and 6 Oxygen atoms. Now to balance the Oxygen atoms, you must multiply the oxygen atoms on the left by 3.

1 P4 + 3 O2 —-> 2 P2O3

Lastly, this equation type is synthesis (combination) because two reactants are becoming a single product.

3 0

2 years ago

Read 2 more answers