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3 years ago

Which of the following could be the name of the substance in box ‘c` choose only one box:

Chemistry

1 answer:

pentagon [3]3 years ago

7 0

I would say carbon monoxide
Firstly because the image shows two different atoms bonded so it cannot be nitrogen or krypton
Secondly sulphur dioxide has 3 atoms bonded (two oxygens and a sulphur atom) so it can’t be that
Finally it can’t be hydrogen chloride because chloride is significantly larger than hydrogen
Thus it must be carbon monoxide as carbon and oxygen are bonded (CO) and are both relatively similar in size

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Acetylene (c2h2) undergoes combustion in excess oxygen to generate gaseous carbon dioxide and water. given δh°f[co2(g)] = –393.5

Brums [2.3K]

Answer is: 13181,7 kJ of energy is released when 10.5 moles of acetylene is burned.
Balanced chemical reaction: C₂H₂ + 5/2O₂ → 2CO₂ + H₂O.
ΔHrxn = sum of ΔHf (products of reaction) - sum of ΔHf (reactants).
Or ΔHrxn = ∑ΔHf (products of reaction) - ∑ΔHf (reactants).
ΔHrxn - enthalpy change of chemical reaction.
ΔHf - enthalpy of formation of reactants or products.
ΔHrxn = (2·(-393,5) + (-241,8)) - 226,6 · kJ/mol.
ΔHrxn = -1255,4 kJ/mol.
Make proportion: 1 mol (C₂H₂) : -1255,4 kJ = 10,5 mol(C₂H₂) : Q.
Q = 13181,7 kJ.

8 0

3 years ago

Be sure to answer all parts. In the average adult male, the residual volume (RV) of the lungs, the volume of air remaining after

Alenkinab [10]

Answer:

For a: The number of moles of air present in the RV is 0.047 moles

For b: The number of molecules of gas is $2.83\times 10^{22}$

Explanation:

For a:

To calculate the number of moles, we use the equation given by ideal gas follows:

$PV=nRT$

where,

P = pressure of the air = 1.00 atm

V = Volume of the air = 1200 mL = 1.2 L (Conversion factor: 1 L = 1000 mL)

T = Temperature of the air = $37^oC=[37+273]K=310K$

R = Gas constant = $0.0821\text{ L. atm }mol^{-1}K^{-1}$

n = number of moles of air = ?

Putting values in above equation, we get:

$1.00atm\times 1.2L=n_{air}\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 310K\\n_{air}=\frac{1.00\times 1.2}{0.0821\times 310}=0.047mol$

Hence, the number of moles of air present in the RV is 0.047 moles

For b:

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of molecules.

So, 0.047 moles of air will contain $(0.047\times 6.022\times 10^{23})=2.83\times 10^{22}$ number of gas molecules.

Hence, the number of molecules of gas is $2.83\times 10^{22}$

7 0

2 years ago

List the number of each type of atom on the left side of the equation 2Na3PO4(aq)+2CoCl2(aq)→2Co3(PO4)2(s)+6NaCl(aq) Enter your

Trava [24]

Answer:

Na(sodium atom) = 6 atoms , P(phosphorus atom) = 2 atoms, Oxygen(Oxygen atom) = 8 atoms , Co(cobalt atom) = 2 atoms, Cl(chlorine atom) = 4 atoms

Explanation:

2Na3PO4(aq) + 2CoCl2(aq) → 2Co3(PO4)2(s) + 6NaCl(aq)

The question ask us to list the number of the kind of atom found on the left side(reactant) of the chemical equation. The question also reiterated that the order of the numbers should be the same as the order of the elements on the left side of the equation.

The type of atoms found on the left side of the equation are as follows;

Na(sodium atom) = 6 atoms

P(phosphorus atom) = 2 atoms

Oxygen(Oxygen atom) = 8 atoms

Co(cobalt atom) = 2 atoms

Cl(chlorine atom) = 4 atoms

The equation on the left hand side have sodium atom, phosphorus atom, oxygen atom, cobalt atom and chlorine atom.

Note: The given equation is not balanced but it can be balanced as follows;

2Na3PO4(aq) + 3CoCl2(aq) → Co3(PO4)2(s) + 6NaCl(aq)

The balanced equation have the following number of atom on the left side:

Na(sodium atom) = 6 atoms

P(phosphorus atom) = 2 atoms

Oxygen(Oxygen atom) = 8 atoms

Co(cobalt atom) = 3 atoms

Cl(chlorine atom) = 6 atoms

5 0

3 years ago

Suppose you used 0.5 M NaOH to titrate your vinegar sample instead of 0.1 M. What effect does the concentration of base added ha

laiz [17]

Answer: the reliability will be worse

Explanation:

Suppose we used 0.5 M NaOH to titrate our vinegar sample instead of 0.1 M.

Now by using 0.5M instead of 0.1M we are increasing the concentration of NaOH,

We know that the moles used = Volume x concnetration.

so for the same no of moles, if the concentration increases, the volume decreases.

Hence it will consume less NaOH.

now Since the volume decreases, the titration volume of less number will increase the % error.

Therefore the reliability will be worse.

4 0

2 years ago

B. Argue: Your classmate predicted the magnets are

rodikova [14]

Answer

they atract

Explanation:

8 0

3 years ago