7. Methane, CH, burns in oxygen gas to form water and carbon dioxide. Wequation for this reaction?a. CH4+ O H2O CO2b. CH4+ 40 2H
20+ CO2c. CH4 O2 H2O CO2d. CH4+ 202 2H20 CO2
8. How many atoms are present in 3 moles of chromium?c. 1.80 x 1024 atomsa. 6.02 x 1023 atomsb. 1.80 x 1023 atomsd. 52.00 atoms
9. How many grams of CO2 are in 2.1 mol of the compound?a. 21.0 gc. 66.0 gb. 44.0 gd. 92.4 g
8. How many atoms are present in 3 moles of chromium?c. 1.80 x 1024 atomsa. 6.02 x 1023 atomsb. 1.80 x 1023 atomsd. 52.00 atoms
9. How many grams of CO2 are in 2.1 mol of the compound?a. 21.0 gc. 66.0 gb. 44.0 gd. 92.4 g
1 answer:
You might be interested in
Answer:
-586.56 kJ/mol is the standard enthalpy of the 3rd reaction.
Explanation:
...[1]
...[2]
..[3]
The unknown standard enthalpy of third reaction can be calculated by using Hess's law:
The law states that 'the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps'.
[2] - 2 × [1] = [3]
The standard enthalpy of the 3rd reaction is -586.56 kJ/mol.The negative sign indicates that energy is released during this reaction.
Answer:
The edge of the length is
Explanation:
From the given information:
The associated energy for a particle in three - dimensional box can be expressed as:
here;
h = planck's constant =
= the quantum no in a specified direction
m = mass (of particle)
L = length of the box
At the ground state
The energy at the ground state can be calculated by using the formula:
At first excited energy level, one of the quantum values will be 2 and the others will be 1.
Thus, the first excited energy will be: 2,1,1
∴
The transition energy needed to move from the ground to the excited state is:
----- (1)
Recall that:
the wavelength identified with the electronic transition is: 800 nm
800 nm = 8.0 × 10⁻⁷ m
However, the energy-related with the electronic transition is:
Replacing the value of in (1); then:
Making the edge length L the subject of the formula; we have:
Thus, the edge of the length is