Measurements show that the enthalpy of a mixture of gaseous reactants increases by 319kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that 92kJ of work is done on the mixture during the reaction. Calculate the change of energy of the gas mixture during the reaction in kJ.

Answer: The empirical formula is [tex]C_{17}H_{19}O_3N[/tex]

Explanation:

Mass of C= 17.900 g

Mass of H = 1.680 g

Mass of O = 4.225 g

Mass of N = 1.228 g

Step 1 : convert given masses into moles.

Moles of C =[tex]\frac{\text{ given mass of C}}{\text{ molar mass of C}}= \frac{17.990g}{12g/mole}=1.5moles[/tex]

Moles of H =[tex]\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{1.680g}{1g/mole}=1.680moles[/tex]

Moles of O =[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{4.225g}{16g/mole}=0.264moles[/tex]

Moles of N =[tex]\frac{\text{ given mass of N}}{\text{ molar mass of N}}= \frac{1.228g}{14g/mole}=0.087moles[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For C = [tex]\frac{1.5}{0.087}=17[/tex]

For H = [tex]\frac{1.680}{0.087}=19[/tex]

For O =[tex]\frac{0.264}{0.087}=3[/tex]

For N = [tex]\frac{0.087}{0.087}=1[/tex]

The ratio of C : H: O: N = 17: 19: 3: 1

Hence the empirical formula is [tex]C_{17}H_{19}O_3N[/tex]

Explanation:

1 mole = 6.02 x 10^23 atoms (Avogadro’s number)

Step 1) Determine how many grams of a substance are in the problem

Step 2) Find the amount of grams in 1 mole of the substance

3) Multiply step one by step two

Answer:

true

Explanation:

Prophase is the first stage in mitosis, occurring after the conclusion of the G2 portion of interphase. During prophase, the parent cell chromosomes which were duplicated during S phase condense and become thousands of times more compact than they were during interphase.

Answer:

1700 mL / 84 mLs

Explanation:

Given that:

Volume of blood pumped per minute = 84 /mLs

Time it takes to circulate 1700 mL of blood :

Time taken = Volume of blood circulate / Rate

Hence, to circulate 1700 mL of blood :

Time taken = 1700 mL / 84 mLs

Answer:

37.7 atm

Explanation:

Using the relation;

(P + an^2/V^2) (V - nb) = nRT

(P + an^2/V^2) = nRT/(V - nb)

a = 0.0341 atm dm^2 Mol^2

b = 0.0237 dm/mol

P = nRT/(V - nb) - an^2/V^2

P = [4.3 * 0.082 * 325 / (3.6 - (4.3 * 0.0237))] - (0.0341 * (4.3^2))/(3.6^2)

P = 114.595/(3.498) - 0.0487

P = 37.7 atm

Answer:

3

Explanation:

2,8,6

Answer:

A: Helium or Hydrogen

Explanation:

Terrestrial planets are the 4 inner most planets of the solar system which are mercury, venus, earth, Mars, while the giant planets are the 4 outer most which are Jupiter, Saturn, Uranus and Neptune.

Now, these outer most ones are the surface ones and are surrounded primarily by layers of hydrogen and helium gases.

Answer:

Ionic Substance is....

Explanation:

In chemistry, an ionic compound is a chemical compound composed of ions held together by electrostatic forces termed ionic bonding. The compound is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions.

Answer:

630.95 grams of Na₂CO₃ would be needed to produce 1000g of NaHCO₃

Explanation:

The balanced reaction is:

Na₂CO₃ + CO₂+ H₂O → 2 NaHCO₃

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:

Being the molar mass:

Then by stoichiometry the following quantities of mass participate in the reaction:

You can apply the following rule of three: if 106 grams of Na₂CO₃ are needed to produce 168 grams of NaHCO₃, how much mass of Na₂CO₃ is necessary to produce 1000 grams of NaHCO₃?

[tex]mass of Na_{2} CO_{3}=\frac{1000grams ofNaHCO_{3} *106gramsofNa_{2} CO_{3} }{168grams ofNaHCO_{3}}[/tex]

mass of Na₂CO₃= 630.95 grams

630.95 grams of Na₂CO₃ would be needed to produce 1000g of NaHCO₃

Answer:

3.0g remain

Explanation:

The half-life is defined as the time required for a reactant to decrease its concentration in exactly the half of the initial amount of reactant. Having this in mind:

In one half-life, the mass will be:

24.0g / 2 = 12.0g

In two half-lifes:

12.0g / 2 = 6.0g

And in three half-lifes, the mass that remain is:

6.0g / 2 =

Answer:

Rocks are classified according to characteristics such as mineral and chemical composition, permeability, texture of the constituent particles, and particle size. This transformation produces three general classes of rock: igneous, sedimentary and metamorphic. Those three classes are subdivided into many groups.

Explanation:

Answer:

feeding leftover or scraps to livestock

Explanation:

Because feeding leftover healthy food instead of leaving livestock to eat garbage is good for health of the animals and they give good quality of milk, eggs, meat, etc in return

Answer:

false

Explanation:

An electric field may do work on a charged particle, while a magnetic field does no work.

Answer:

Rate = k[NH₄OH]²

k = 6.17

Explanation:

We have concentrations of NH₄OH along with the given times. To determine the rate law of the reaction we need to determine first the order of reaction. This reaction can be order zero, first or second order. The expressions for each are the following:

Zero order:

k = [A₀] - [A] / t

First order:

k = 1/t * ln([A₀]/[A])

Second order:

k = (1/t) * (1/[A₀] - 1/[A])

And from here, the next part is easier. We just need to determine hat order is, calculating the value of k at two different times. If the value of k is constant, then we can say that the reaction is of that order.

Let's suppose its order zero (t = 1 and t = 2, [A₀] = 0.200 M):

k1 = 0.2 - 0.0895 / 1 = 0.1105

k2 = 0.2 - 0.577 / 2 = -0.1885

From this results we can conclude it's not zero order.

Let's suppose its order 1:

k1 = ln(0.2/0.0895) / 1 = 0.8041

k2 = ln(0.2/0.577) / 2 = 0.1733

It's not first order either, so we can conclude that this reaction is of 2nd order and the rate law would be:

Now that we know it's a second order reaction, we can determine the value of k using its expression:

k = (1/t) (1/[A] - 1/[A₀])

k = ln(1/0.0895 - 1/0.2) (1/1)

k = 6.17

And to confirm this value, let's calculate k for t = 2 s

k = (1/2) (1/0.0577 - 1/0.2)

The value is constant, so this is the true value of k.

Hope this helps

Answer: The vapor pressure of a solution in which the mole fraction of the solute is 0.200 is 80.0 torr

Explanation:

As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.

The formula for relative lowering of vapor pressure will be,

[tex]\frac{p^o-p_s}{p^o}=i\times x_2[/tex]

where,

[tex]p^0[/tex]= vapor pressure of pure solvent = 100.0 torr

[tex]p_s[/tex] = vapor pressure of solution = ?

i = Van'T Hoff factor = 1 for nonvolatile, nonelectrolyte solute

[tex]x_2[/tex] = mole fraction of solute  = 0.200  

[tex]\frac{100.0-p_s}{100.0}=1\times 0.200[/tex]

[tex]p_s=80.0torr[/tex]

The vapor pressure of a solution in which the mole fraction of the solute is 0.200 is 80.0 torr

Answer:

65.0cp

Explanation:

Answer:

H^+(aq) + OH^-(aq) --------> H2O(l)

Explanation:

We must first obtain the molecular equation, the net ionic equation before we obtain the net ionic equation.

The molecular reaction equation is;

HF(aq) + NaOH(aq) -------> H2O(l) + NaF(aq)

The complete ionic equation is;

H^+(aq) + F^-(aq) + Na^+(aq) + OH^-(aq) --------> H2O(l) + Na^+(aq) + F^-(aq)

The net ionic equation is;

H^+(aq) + OH^-(aq) --------> H2O(l)

Answer: A chemical compound can be described as substance composed of atoms from more than one element held together by chemical bonds in a fixed stoichiometric proportion. A compound has different physical and chemical properties from its constituent elements.

For example : compound water is made up of H and O bonded together and it has different properties from O and H.

Thus, among the given options, the one coreectly describing a compound is

a) The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.

Answer:

4 is the answer

Explanation:

i am not sure for this question

Answer:

Released

Explanation:

they convert into a form of energy that can be used by cells

Answer: 0.0450 moles of [tex]CaCl_2[/tex]

Explanation:

According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]

[tex]\text{Number of moles of} CaCl_2=\frac{5.00g}{110.98g/mol}=0.0450moles[/tex]

Thus there are 0.0450 moles of [tex]CaCl_2[/tex]

Answer:

That is the Atomic mass

Explanation:

The element symbol is S, Element name is sulfur, and

Atomic number is 16

Answer:

Follows are the solution to this question:

Explanation:

Please find the complete solution in the attached file.

Answer:

No pain, no gain is a proverb that means in order to make progress or to be successful, one must suffer. This suffering may be in a physical or mental sense. The phrase no pain, no gain was popularized in the 1980s by the American actress, Jane Fonda.