Answer:
When the graduation line denotes the volume contained in the calibrated vessel, the ware is marked “TC”. When the graduation line indicates the volume delivered from the vessel, the ware is marked “TD”.
When a student mixes 5.00 g of NH4NO3 with 50.0 mL of water in a coffee-cup calorimeter, the temperature of the resultant solution decreases from 22.0 °C to 16.5 °C. Assume the density of water is 1.00 g/ml and the specific heat capacity of the resultant solution is 4.18 J/g·°C.
1) Calculate q for the reaction. You must show your work.
2) Calculate the number of moles of NH4NO3(s) which reacted. You must show your work.
3) Calculate ΔH for the reaction in kJ/mol. You must show your work.
Answer:
Explanation:
NH₄NO₃ = NH₄⁺ +NO₃⁻
heat released by water = msΔ T
m is mass , s is specific heat and ΔT is fall in temperature
= 50 x 4.18 x ( 22 - 16.5 ) ( mass of 50 mL is 50 g )
= 1149.5 J .
This heat will be absorbed by the reaction above .
q for the reaction = + 1149.5 J
2 )
molecular weight of NH₄NO₃ = 80
No of moles reacted = 5/80 = 1 / 16 moles.
3 )
5 g absorbs 1149.5 J
80 g absorbs 1149.5 x 16 J
= 18392 J
= 18.392 kJ.
= + 18.392 kJ
ΔH = 18.392 kJ / mol
Answer:
so the reaction rate increases by a factor 6.
Explanation:
For the given equation the reaction is first order with respect to both ester and sodium hydroxide
So we can say that the rate law is
now as per given conditions the concentration of ester is increased by half it means that the new concentration is 1.5 times of old concentration
The concentration of NaOH is quadrupled means the new concentration is 4 times of old concentration.
The new rate law is
the final rate = 6 X initial rate
so the reaction rate increases by a factor 6.
Answer:
The activation energy is
Explanation:
The gas phase reaction is as follows.
The rate law of the reaction is as follows.
The reaction is carried out first in the plug flow reactor with feed as pure reactant.
From the given,
Volume "V" =
Temperature "T" = 300 K
Volumetric flow rate of the reaction
Conversion of the reaction "X" = 0.8
The rate constant of the reaction can be calculate by the following formua.
Rearrange the formula is as follows.
The feed has Pure A, mole fraction of A in feed is 1.
= change in total number of moles per mole of A reacte.
Substitute the all given values in equation (1)
Therefore, the rate constant in case of the plug flow reacor at 300K is
The rate constant in case of the CSTR can be calculated by using the formula.
The feed has 50% A and 50% inerts.
Hence, the mole fraction of A in feed is 0.5
= change in total number of moles per mole of A reacted.
Substitute the all values in formula (2)
Therefore, the rate constant in case of CSTR comes out to be
The activation energy of the reaction can be calculated by using formula
In the above reaction rate constant at the two different temperatures.
Rearrange the above formula is as follows.
Substitute the all values.
Therefore, the activation energy is
Answer:
You could collect the mixture and pour it in water, stir it , ad filter out the sand. This uses the physical property of solubility.
Explanation:
The salt dissolved, the sand didn't.
Answer:
2.6 sec
Explanation:
The distance between the Earth and the moon = 240,000 miles
Also,
1 mile = 1609.34 m
So,
Distance between the Earth and the moon = 240,000 × 1609.34 m = 386241600 m
Speed of the light = 3 × 10⁸ m/s
Distance = Speed × Time.
So,
Time = Distance / Speed = 386241600 m / 3 × 10⁸ m/s = 1.3 sec
For back journey = 1.3 sec
So, total time = 2.6 sec
When Americium (Am-241) undergoes alpha decay(He-4) it forms neptunium (Np-237) based on the following pathway:
²⁴¹Am₉₅ → ²³⁷Np₉₃ + ⁴He₂
The energy released in given as:
ΔE = Δmc²
where Δm = mass of products - mass of reactants
= [m(Np-237) + m(He-4)] - [m(Am-241)]
= 237.0482+4.0015-241.0568 = -0.0073 g/mol = -7.3 * 10⁻⁶ kg/mol
ΔE = -7.3*10⁻⁶ kg/mol * (3*10⁸ m/s)² = -5.84*10¹¹ J/mol