Answer:
B. Elements with two or eight valence electrons.
Answer:
m = 65.637 g
Explanation:
Heat = 0.612 kJ = 612 J ( Converting to J by multiplying by 1000)
Initial Temperature = 30.°C
Final Temperature = 51°C
Temperature change = Final Temperature - Initial Temperature = 51 - 30 = 21°C
Mass = ?
The relationship between these quantities is given by the equation;
H = mCΔT
where c = 0.444 J/g°C
Inserting the values in the equation;
612 = m * 0.444 * 21
m = 612 / (0.444 * 21)
m = 65.637 g
My answer would be b. hope this helps.
The molar concentration of potassium ions in a 0. 250 m K₂SO₄(aq) solution is 2.
<h3>What is molar concentration?</h3>
The molar concentration of a solution is the presence of solute in one unit of a solution.
Molar concentration = number of moles / volume
The volume is given 0.250 m
To calculate the number of moles:
There will be 2 moles of potassium and 1 mole of sulfate in one L of the solution.
So in 0.250 L
0.250 x 2 x 1 = 0.500
The total number of moles of potassium and sulfate ion are 0.500
Now, putting the value:
Molar concentration = number of moles / volume
0.500 / 0.250 = 2
Thus, the molar concentration is 2.
To learn more about molar concentration, refer to the below link:
brainly.com/question/21841645
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