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3 years ago

Based on the molar masses, how can you tell that an equation is balanced?

2 answers:

7 0

When you work with molar mass, you solve for the quantity of ''Moles'' within the substance by converting Mass. The way you can tell the equation is balanced would be by knowing whether the moles were equivalent on both sides or not. Therefore, if they are equal, it is balanced considering you have the same amount of moles on each side of the equation.

Rashid [163]3 years ago

5 0

Explanation :

According to the law of conservation of mass, the mass of reactant must be equal to the mass of product. That means mass remains conserved.

Based on the molar masses, we can tell that an equation is balanced or not.

If the sum of the molar mass of reactant side will be equal to the sum of the molar mass of product side then we can tell that an equation is balanced otherwise an equation is not balanced.

For example : $2Na+2H_2O\rightarrow 2NaOH+H_2$

Now we have to check that this reaction is balanced or not.

As per law of conservation of mass,

Sum of molar mass of reactant = Sum of molar mass of product

$2Na+2H_2O=2NaOH+H_2$

The molar mass of sodium(Na), hydrogen(H) and oxygen(O) are 23, 1 and 16 g/mole respectively.

$2(23)+2(2\times 1+16)=2(23+16+1)+2(1)$

$82=82$

The mass of reactant side is equal to the product side that means this equation is balanced.

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What do you know about Relative Dating

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it tells you the sequence in which events occurred, not how long ago they occurred.

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3 years ago

If a pork roast must absorb kJ to fully cook, and if only 10% of the heat produced by the barbecue is actually absorbed by the r

kolezko [41]

Answer:

1,033.56 grams of carbon dioxide was emitted into the atmosphere.

Explanation:

$C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g),\Delta H_{rxn}=-2044 kJ/mol (assuming)$

Energy absorbed by pork,E = $1.6\times 10^3 kJ$ (assuming)

Total energy produced by barbecue = Q

Percentage of energy absorbed by pork = 10%

$10\%=\frac{E}{Q}\times 100$

$Q=\frac{E}{10}\times 100=\frac{1.6\times 10^3 kJ}{10}\times 100=1.6\times 10^4 kJ$

Since, it is a energy produced in order to indicate the direction of heat produced we will use negative sign.

Q = $-1.6\times 10^4 kJ$

Moles of propane burnt to produce Q energy =n

$n\times \Delta H_{rxn}=Q$

$n=\frac{Q}{\Delta H_{rxn}}=\frac{-1.6\times 10^4 kJ}{-2044 kJ/mol}=7.83 mol$

According to reaction , 1 mol of propane gives 3 moles of carbon dioxide. then 7.83 moles of will give:

$\frac{1}{3}\times 7.83 mol=23.49 mol$ carbon dioxide gas.

Mass of 23.49 moles of carbon dioxide gas:

23.49 mol × 44 g/mol =1,033.56 g

1,033.56 grams of carbon dioxide was emitted into the atmosphere.

8 0

2 years ago

Which process involves an increase in entropy? crystallization of a solute from a solution ice melting into liquid water iodine

GrogVix [38]

Ice melting into liquid water.

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3 years ago

Read 2 more answers

The graphics below shows how photosynthesis and cellular respiration are related.

lisov135 [29]

Options found from another source are:

a. oxygen. b. glucose. c. energy stored as ATP. d. carbon dioxide and water

Answer:

c energy stored as ATP

Explanation:

Cellular respiration converts glucose into energy in the form of ATP (c). The answer cannot be oxygen (a), because this is required for this process as a final electron acceptor. In terms of photosynthesis, oxygen is released as a by-product. The answer cannot be glucose (b) because that is our starting point for respiration, and what is synthesised during photosynthesis. The answer cannot be (d) as carbon dioxide and water are released by cellular respiration, and required by photosynthesis

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3 years ago

Use the standard reaction enthalpies given below to determine ΔH°rxn for the following reaction:P4(g) + 10 Cl2(g) → 4PCl5(s) ΔH°

miskamm [114]

Answer: The $\Delta H^o_{rxn}$ for the reaction is -1835 kJ.

Explanation:

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The given chemical reaction follows:

$P_4(g)+10Cl_2(g)\rightarrow 4PCl_5(s)$ $\Delta H^o_{rxn}=?$