the chemical equation for reduction of phosphorite Ca3(PO4)2

Answer:

The enthalpy change (∆H) for the reaction is -108.7 kJ

Explanation:

Hess's law can be stated as: when the reactants are converted to products, the enthalpy change is the same, regardless of whether the reaction is carried out in one step or in a series of steps. Then, Hess's Law states that the enthalpy of one reaction can be achieved by algebraically adding the enthalpies of other reactions.

So,  to calculate the ∆H (heat of reaction) of the combustion reaction, that is, the heat that accompanies the entire reaction, you must make the total sum of all the heats of the products and of the reagents affected by their stoichiometric coefficient ( number of molecules of each compound participating in the reaction) and finally subtract them.

Enthalpy of combustion = ΔH = ∑Hproducts - ∑Hreactants

2 ClF + O₂ → Cl₂O + F₂O ∆H=167.4kJ

Cl₂O + 3 F₂O → 2 ClF₃ + 2 O₂ ∆H= -341.4kJ  

The previous equation must be inverted, and the enthalpy value is also inverted, that is, the sign is changed.

2 F₂ + O₂ →2 F₂O ∆H=-43.4kJ

Reactants and products are added or canceled, taking into account that certain substances sometimes appear as a reagent and others as a product, so they are totally eliminated (there is nothing left of them anywhere in the reaction, if the same amount in reagents and products) or partially (this substance remains, in less quantity, only on one side), obtaining:

2 ClF + 2 F₂ → 2 ClF₃

Then, as all the reactants and products have a stoichiometric coefficient of 2, dividend by that number is obtained:

ClF + F₂ → ClF₃

Adding the enthalpies algebraically, and dividing by 2, because to get the "data" reaction you had to multiply by two, you get:

ΔH= [167.4 kJ - 341.4 kJ - 43.3 kJ]÷2

ΔH= -108.7 kJ

The enthalpy change (∆H) for the reaction is -108.7 kJ

Answer:

72.8°C

Explanation:

Step 1:

Data obtained from the question. This include the following:

Specific heat capacity (C) = 0.24J/g°C

Mass (M) = 15g

Heat (Q) = 262J

Change in temperature (ΔT) =..?

Step 2:

Determination of the change in temperature.

The change in temperature, ΔT can be obtained as follow:

Q = MCΔT

262 = 15 x 0.24 x ΔT

Divide both side by 15 x 0.24

ΔT = 262 / (15 x 0.24)

ΔT = 72.8°C

Therefore, the change in temperature, ΔT is 72.8°C

Answer:

a salt

Explanation:

compounds are made of molecules but we need to mention the type of compound formed.

Answer:

A salt

Because compounds are made of molecules but we need to mention the type of compound formed.

Answer:

C)We cannot be sure unless we find out its boiling point.

Explanation:

It is necessary to clearly explain here that simply observing two compounds of the same homologous series irrespective of how close they may be in the series will not give us the faintest idea regarding which one will be a liquid, solid or gas at room temperature.

However, to determine whether an unknown substance will be a liquid at room temperature, then its important to measure its boiling point. If the boiling point is above room temperature, and the melting point is below room temperature, the compound is a liquid. If the boiling point of the unknown substance is below room temperature, it is a gas.

It is now safe to conclude that cannot decide on the state of matter in which a compound exists unless we know something about its boiling point, not merely looking closely at the properties of its neighbouring compounds in the same homologous series

Answer:

gas and liquid

Explanation:

right?

Answer:

Choice D. Approximately [tex]61.2[/tex] minutes.

Explanation:

The reaction rate of a second-order reaction is proportional to the square of one of its reactants.

Let [tex]k[/tex] denote the rate constant of this reaction. Assume that [tex]y_0[/tex] is the concentration of that reactant at the beginning of this reaction (when [tex]t = 0[/tex].) Because this reaction is of second order, it can be shown that:

[tex]\displaystyle y = \frac{1}{k\, t + (1/y_0)}[/tex].

The question states that the rate constant here is [tex]0.06\; \rm M\cdot min^{-1}[/tex]. Hence, [tex]k = 0.06[/tex]. For simplicity, assume that [tex]t = 0[/tex] when the concentration is [tex]0.13\; \rm M[/tex]. Therefore, [tex]y_0 = 0.13[/tex]. The equation for concentration [tex]y[/tex] at time [tex]t[/tex] would become:

[tex]\displaystyle y = \frac{1}{\underbrace{0.06}_{k}\, t + (1/\underbrace{0.13}_{y_0})}[/tex].

The goal is to find the time at which the concentration is [tex]0.088[/tex]. That's the same as solving this equation for [tex]t[/tex], given that [tex]y = 0.088[/tex]:

[tex]\displaystyle \frac{1}{0.06\; t + (1/0.13)} = 0.088[/tex].

[tex]t \approx 61.2[/tex].

In other words, it would take approximately [tex]61.2[/tex] minutes before the concentration of this second-order reactant becomes [tex]0.088\; \rm M[/tex].

Answer:

d

Explanation:

Explanation:

The states may differ depending on the reactions

Answer:

Empirical formula is Na₂CO₃

Molecular formula is Na₂CO₃

Explanation:

Percentage compositions of the elements;

Sodium = 46%

Carbon = 12 %

Oxygen = 42%

To determine empirical formula, we calculate the mole ratio first.

mole ratio =  % mass/atomic mass; where the atomic masses of the elements are :  Na = 23 u, C = 12 u and O = 16 u.

mole ratio: Na = 46/23; C = 12/12; O = 42/16

mole ratio (Na : C : O) = 2 : 1 : 2.6

approximate mole ratio = 2 : 1 :3

Therefore, empirical formula of compound is Na₂CO₃

To determine the molecular formula;

molecular formula or mass = n(empirical formula or mass)

n = molecular mass/empirical mass

molecular mass = 106 u,

empirical mass = 23*2 + 12 + 16*3 = 106 u

then, n = 106/106 = 1

therefore, molecular formula = 1 * (Na₂CO₃) = Na₂CO₃

Answer: Alex should get 300 Calories from carbohydrates, which is about 33 grams. This snack is almost 70% of her total grams of carbohydrates per day.

Answer:

B

Explanation:

I think

Answer:

c

Explanation:

I would think adapting to changes would be the light moth being in a light trunk of a trees.

Answer:

a

Explanation:

dark colored moths become common after tree trunks become dark took the test.

Answer:

No. 4

Explanation:

Bacteria are produced from pre existing bacteria

Answer:

2KClO₃→3O₂ + 2KCl

Explanation:

When Potassium Chlorate decomposes , the resulting products are oxygen gas and Potassium chloride . As per the equation above

Answer:

See below

Explanation:

The common formula of the same alkene series is CnH2n, where n is the quantity of atoms of carbon. Owing to the hydrocarbons of alkenes with at least one double carbon relation, the alkene-like sequence starts with ethen C2H4.

Hope this helps.

The general formula for the homologous series which includes ethene is alkenes.

Alkenes

They are homologous series with the general formula CxH2x.

Where:

x = number of carbon atoms.

Examples are methene with one carbon atom: CH2

Ethene with 2 carbon atoms: C2H4

Propene with 3 carbon atoms: C3H6

More on alkenes can be found here: https://brainly.com/question/7337516

Answer:

The second one is correct

Explanation:

Because reactants are sth that attend in a reaction and can make sth like (MgO) of course in this question. For example in this reaction : H+ClHCl. That H and Cl are reactants

Good luck

Answer:

Alkaline

Explanation:

The solution of ash of magnesium ribbon is alkaline.

Answer:

The smell of a chocolate is from the presence of volatile compounds present in the chocolate bar which at room temperature readily changes phase from solid to liquid to vapor or gas

Explanation:

There are nearly 600 identified compounds present in a chocolate bar and out of these, there are volatile components which gives the chocolate bar its distinctive aroma.

These volatile chocolate contents readily change phase from solid to vapor, with very short duration liquid phase.

For example, 3 methylbutanal, vanillin, and several organic compounds which are known to be readily volatile.

Answer:

54.1°C

Explanation:

Now we have the following parameters from the question;

Heat applied (H)= 18.0×10^3 Joules

Mass of the water(m)= 250g= 0.25Kg

Initial temperature of the water (θ1)= 37°C

Final temperature of the water (θ2)= the unknown

Heat capacity of water (c) = 4200JKg-1

From ;

H= mc(θ2-θ1)

Substituting values appropriately

18×10^3= 0.25 × 4200(θ2-37)

18×10^3 = 0.25 × (4200θ2 - 155400)

18×10^3 = 1050θ2 - 38850

18×10^3 + 38850 = 1050θ2

56850 = 1050θ2

θ2= 56850/1050

θ2= 54.1°C

Answer:

7

Explanation:

1/3 of 21 is also the same as 21/3, which is 21 divided by 3

So the right answer is 7.

please see attached picture for full solution

hope it helps

Good luck on your assignment

Answer:

I hope this will help its not much

Explanation:

Answer:

Functional groups are important in chemistry because they are the portion of a molecule that is capable of characteristic reactions.

Explanation:

Answer:

pls help

Explanation:

Answer:

4m/s² north.

Explanation:

Data obtained from the question include the following:

Mass (m) = 10Kg

Force (F) = 40N North.

Acceleration (a) =...?

Force is simply the product of mass and acceleration. It is represented mathematically as:

Force (F) = Mass (m) x acceleration (a)

F = ma

With the above formula, we can obtain the acceleration of the object as follow:

40 = 10 x a

Divide both side by 10

a = 40/10

a = 4m/s²

Since the force was applied in the north direction, the object will also accelerate in the north direction. Therefore, the acceleration of the object is 4m/s² north.

Answer:

pH + pOH = 14,  [H₃0⁺] [0H⁻] = 10⁻¹⁴

Explanation:

When it comes to questions involving pH, the equations used are;

[H₃0⁺] [0H⁻] = 10⁻¹⁴

This equation shows the concentration of hydroxonium ions alongside that of the hydroxide ions.

pH + pOH = 14

If the value of either the pH of the pOH is know,one can calculate the value of the other using this equation.

Answer:

The answer is A. The pOH of the solution is 12.0

Explanation:

The formula for pOH is:

pOH = 14 - pH

We know that the pH value is 2.0 so we plug it in the equation:

pOH = 14 - (2.0)

After simplifying it, we get an answer of 12.0 which is the pOH value.

Hope this helps!

Answer:

Respiration

Explanation:

it is the process by which food is broken down in the cell to release energy

Answer:

Butanoic acid

Explanation:

Answer:

613.0 g

Explanation:

2 L = 2000 mL

(30.65 g/100 mL)*2000 mL = 613.0 g

Given:

Solution:

Firstly,

We converted L to mL

2 L = 2 × 1000 mL = 2000 mL [ 1 L = 1000 mL ]

Now,

Solute = 30.65/100 × 2000

= 30.65 × 2000 / 100

= 61,300/100

= 613