Answer:
B and C is your answer
Explanation:
Hope I helped, Sorry if I'm wrong
Answer:
17.76g
Explanation:
We need to write a balanced chemical equation for the reaction:
2Al(OH)3 + 3Ca(NO3)2 ——> 3Ca(OH)2 + 2Al(NO3)3
In the reaction above, it can be seen that 2 moles of aluminum hydroxide yielded 3 moles of calcium hydroxide. This is the theoretical viewpoint.
Now we need to know what actually happened. We need to calculate the actual number of moles of aluminum hydroxide reacted l. We can get this by dividing the mass by the molar mass.
The molar mass of aluminum hydroxide is 27+ 3( 16+1)
= 27 + 51 = 78g/mol
The number of moles is thus: 12.55/78 = 0.16 moles
Now if 2 moles of aluminum hydroxide gave 3 moles of calcium hydroxide, 0.16moles will give : (0.16*3)/2 = 0.24moles
Now we can calculate the mass of calcium hydroxide formed. The mass of calcium hydroxide formed is the number of moles multiplied by the molar mass.
The molar mass of calcium hydroxide is; 40 + 2(17) = 74g/mol
The mass is thus =74 * 0.24 = 17.76g
Water has a molar mass of 18.015 g/mol . This means that one mole of water molecules has a mass of 18.015 g . So, to sum this up, 6.022⋅1023 molecules<span> of water will amount to 1 mole of water, which in turn will have a mass of 18.015 g . 2.7144moles H2O ⋅</span>6.022<span>⋅1023molec.1mole H2O =1.635⋅1024molec.</span>
Answer:
D
Explanation:
It is also known as the Dalton’s law of partial pressure. Given a confinement that contains a mixture of gases which do not mix, the total pressure equals the sum of the individual pressures.
The term, which do not mix is necessary because, if the gases are the type that mix, the law will no longer hold as they would have given up their individual identities and hence their individual partial pressure cannot be use to access them anymore.
Hence, the law helps to sum the totality of the pressures of a number of gases which exists together in a confinement and they do not mix. Say we have 3 gases A, B and C. The total pressure is the sum of pressure A, pressure B and pressure C.
Answer:
1.25 M HCO₃⁻ / 1.25 M CO₃²⁻
Explanation:
Buffer capacity refers to the amount of a strong acid or base required per liter of the buffer to change its pH by one. This amount is directly related to the concentration of the conjugate acid-base pair in the buffer since the buffer pair neutralizes the strong acid or base.
Thus, the highest buffer capacity is found in the solution that has the highest concentration of the conjugate acid-base pair, which is 1.25 M HCO₃⁻ / 1.25 M CO₃²⁻
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