As long as the equation in question can be expressed as the sum of the three equations with known enthalpy change, its 
can be determined with the Hess's Law. The key is to find the appropriate coefficient for each of the given equations.
Let the three equations with given be denoted as (1), (2), (3), and the last equation (4). Let 
, 
, and 
be letters such that 
. This relationship shall hold for all chemicals involved.
There are three unknowns; it would thus take at least three equations to find their values. Species present on both sides of the equation would cancel out. Thus, let coefficients on the reactant side be positive and those on the product side be negative, such that duplicates would cancel out arithmetically. For instance, 
shall resemble the number of 
left on the product side when the second equation is directly added to the third. Similarly
Thus
and
Verify this conclusion against a fourth species involved- 
for instance. Nitrogen isn't present in the net equation. The sum of its coefficient shall, therefore, be zero.
Apply the Hess's Law based on the coefficients to find the enthalpy change of the last equation.
Moles of N2O5 = moles of NO2 * ( 2 moles of N2O5 / 4 moles of NO2
The mass of oxygen collected from the thermal decomposition of potassium chlorate at a temperature of 297 K and 762 mmHg is 0.16 g
<h3>How to determine the mole of oxygen produced </h3>
We'll begin by obtaining the number of mole of oxygen gas produced from the reaction. This can be obtained by using the ideal gas equation as illustrated below:
- Volume (V) = 0.128 L
- Temperature (T) = 297 K
- Pressure (P) = 762 – 22.4 = 739.6 mmHg
- Gas constant (R) = 62.363 mmHg.L/Kmol
- Number of mole (n) =?
PV = nRT
739.6 × 0.128 = n × 62.363 × 297
Divide both sides by 62.363 × 297
n = (739.6 × 0.128) / (62.363 × 297)
n = 0.0051 mole
Thus, the number of mole of oxygen gas produced is 0.0051 mole
<h3>How to determine the mass of oxygen collected</h3>
Haven obtain the number of mole of oxygen gas produced, we can determine the mass of the oxygen produced as follow:'
- Mole = 0.0051 mole
- Molar mass of oxygen gas = 32 g/mole
- Mass of oxygen =?
Mole = mass / molar mass
0.0051 = mass of oxygen / 32
Cross multiply
Mass of oxygen = 0.0051 × 32
Mass of oxygen = 0.16 g
Thus, we can conclude that the mass of oxygen gas collected is 0.16 g
Learn more about ideal gas equation:
brainly.com/question/4147359
#SPJ1
Answer:
Counting the number of colonies that arise on a pour plate can calculate the concentration by multiplying the count by the volume spread on the pour plate. Direct counting methods are easy to perform and do not require highly specialized equipment, but are often slower than other methods
Explanation:
I hope it will help you
Answer:
The answer would be C. Number of protons in the atom.
Explanation:
On the periodic table, you see the element, with a big number at top, and a small number below the element name/abbreviation.
The big number is the amount of protons of the atom, which define each atom. The smaller number represents the atomic mass of the atom.
#teamtrees #WAP (Water And Plant)
:
:
:
