The solution for this problem is:
The information given lacks but nevertheless the answer is:
So, the total heat free by dissolving the solute was 1386 + 32 = 1417 J
Then, dissolving of the solute will have released -1417 J. So, per gram of Al2
(SO4)3 dissolved:
-1417 J / 25 g = -56.7 J/g
Translating that to a per mole: -56.7 J/g X 342 g/mol = -1.94X10^4 J/mol = -19
kJ/mol = this would be Delta Hsoln
Answer:
Moles = 0.271 mol
Solution:
Step 1: Calculate Mass of Br₂ as;
Density = Mass ÷ Volume
Solving for Mass,
Mass = Density × Volume
Putting values,
Mass = 3.12 g.mL⁻¹ × 13.9 mL
Mass = 43.36 g
Step 2: Calculate Moles of Br₂ as;
Moles = Mass ÷ M.Mass
Putting values,
Moles = 43.36 g ÷ 159.80 g.mol⁻¹
Moles = 0.271 mol
Answer:
B. Periods
Explanation:
The horizontal rows in the periodic table are periods.
on the picture below, u can see an example
Buffers - mixtures of conjugate acid and conjugate base at ±1 pH unit from pH = pKa. Resistant to changes in pH in response to small additions of H+ or OH-. ... Polyprotic acids - dissociation of each H+ can be treated separately if the pKa values are different
I bottle:
250 * 150mg = 37500mg
If 37500mg ------- cost ------- <span> $2.95
so 1mg ------- cost ------- x
x = 1mg*</span> $2.95 / 37500mg = $7,87*10⁻⁵
II bottle
125 * 200mg = 25000mg
If 25000mg ---------- cost ---------- <span>$3.50
so 1mg ---------- cost ---------- x
x = 1mg* </span>$3.50 / 25000mg = $0,00014=$1,4*10⁻⁴
$7,87*10⁻⁵ < $1,4*10<span>⁻⁴
</span>
1st bottle is better bargain cause 1mg of aspirin its cheaper than in 2nd.
