Answer:
Explanation:
Equation of the reaction:
NaOH + HCl --> NaCl + H2O
Volume of HCl = 5 ml
Molar concentration = 1 M
Number of moles = molar concentration * volume
= 1 * 0.005
= 0.005 mol of HCl
By stoichiometry, 1 mole of HCl completely neutralizes 1 mole of NaOH
Therefore, number of moles of NaOH = 0.005 mol
Molar mass of NaOH = 23 + 16 + 1
= 40 g/mol
NaOH --> Na+ + OH-
Mass = molar mass * number of moles
= 40 * 0.005
= 0.2 g of Na+
<u>Answer:</u> The final temperature of the copper is 95°C.
<u>Explanation:</u>
To calculate the final temperature for the given amount of heat absorbed, we use the equation:
Q = heat absorbed = +133 J (heat is added to the system)
m = mass of copper = 5.00 g
c = specific heat capacity of copper = 0.38 J/g ° C
Putting values in above equation, we get:
Hence, the final temperature of the copper is 95°C.
The full question asks to decide whether the gas was a specific gas. That part is missing in your question. You need to decide whether the gas in the flask is pure helium.
To decide it you can find the molar mass of the gas in the flask, using the ideal gas equation pV = nRT, and then compare with the molar mass of the He.
From pV = nRT you can find n, after that using the mass of gass in the flask you use MM = mass/moles.
1) From pV = nRT, n = pV / RT
Data:
V = 118 ml = 0.118 liter
R = 0.082 atm*liter/mol*K
p = 768 torr * 1 atm / 760 torr = 1.0105 atm
T = 35 + 273.15 = 308.15 K
n = 1.015 atm * 0.118 liter / [ 0.082 atm*liter/K*mol * 308.15K] =0.00472 mol
mass of gas = mass of the fask with the gas - mass of the flasl evacuated = 97.171 g - 97.129 g = 0.042
=> MM = mass/n = 0.042 / 0.00472 = 8.90 g/mol
Now from a periodic table or a table you get that the molar mass of He is 4g/mol
So the numbers say that this gas is not pure helium , because its molar mass is more than double of the molar mass of helium gas.
Lets say foxes hunt rabbits. If their are too many foxes then they will compete for the rabbits. The rabbits get outnumbered by the amount of foxes so the foxes kill all the rabbits and the rabbits could eventually go extinct.
Answer:
A. The average of all the data points
