Answer:
Please see the attached pictures.
Explanation:
☆ To ensure that each carbon has 4 bonds, fill the other bonds with Hs.
69. The student's skin was obviously warmer than the initial temperature of the bracelet. According to the second law of thermodynamics, heat transfers from a higher temperature to a lower temperature hence heat transfers from the student's skin to the bracelet warming up the bracelet.
70. moles of copper=mass of copper/molar mass of copper
=30.1g/(63.55g/mol)= 0.4736 moles Cu
71. Delta H( heat released) = mCp(deltaT) = 30.1g(0.385 J/gK)(33-19)K = 162.23J
72. Copper is chemically less active than iron.
Answer:
Mean Partial pressure of Nitrogen in Mars' atmosphere = 15.86 Pa
Explanation:
According to Dalton's law of Partial Pressure, the total pressure exerted by a mixture of ideal gases (that do not react together) is the sum of the partial pressures of the individual gases that make up the mixture. It goes further to explain that the partial pressure of a gas in a mixture of gases is equal to its mole fraction of that gas multipled by the total pressure exerted by the mixture of gases.
Total Pressure exerted by the mixture of gases in the atmosphere on Mars = Mean atmospheric pressure on Mars = 610 Pa
Partial pressure of Nitrogen = (mole fraction or mole percentage of Nitrogen in the atmosphere) × (total pressure exerted by all the gases in the atmosphere)
Mole percentage of Nitrogen in the atmosphere of Mars = 2.6%
Partial pressure of Nitrogen = 2.6% × 610 = 15.86 Pa
Mean Partial pressure of Nitrogen in Mars' atmosphere = 15.86 Pa
Hope this Helps!!!
Answer:
2.893 x 10⁻³ mol NaOH
[HCOOH] = 0.5786 mol/L
Explanation:
The balanced reaction equation is:
HCOOH + NaOH ⇒ NaHCOO + H₂O
At the endpoint in the titration, the amount of base added is just enough to react with all the formic acid present. So first we will calculate the moles of base added and use the molar ratio from the reaction equation to find the moles of formic acid that must have been present. Then we can find the concentration of formic acid.
The moles of base added is calculated as follows:
n = CV = (0.1088 mol/L)(26.59 mL) = 2.892992 mmol NaOH
Extra significant figures are kept to avoid round-off errors.
Now we relate the amount of NaOH to the amount of HCOOH through the molar ratio of 1:1.
(2.892992 mmol NaOH)(1 HCOOH/1 NaOH) = 2.892992 mmol HCOOH
The concentration of HCOOH to the correct number of significant figures is then calculated as follows:
C = n/V = (2.892992 mmol) / (5.00 mL) = 0.5786 mol/L
The question also asks to calculate the moles of base, so we convert millimoles to moles:
(2.892992 mmol NaOH)(1 mol/1000 mmol) = 2.893 x 10⁻³ mol NaOH
Answer:
a)<em> Balanced equation:</em>
An equation is called balanced if there are same number and same type of atom on both sides of the equation.
b)<em>Reason:</em>
2KClO3--------2KCl + 3O2
Consider this equation in the reactants there are 2KClO3 and in the product there are 2KCl+3O2 . So reactants =products which is a case of balanced chemical equation .
Explanation:
