Heat_1: Get the ice to 0 degrees
Convert 7 kg to grams
7 kg [1000 grams / 1 kg] = 7000 grams
Heat needed to get the the ice from - 9 to 0
deltat = 0 - -9 = 9 degrees
m = 7000 grams
c = 2.1 joules/gram
Heat_1 = m*c*deltat
Heat_1 = 7000 * 2.1 * 9
Heat_1 = 132,300 joules
Heat_2: Melt the ice.
There is no temperature change. The formula is 333 j/gram
Formula: H = mass * constant
H = 7000 g * 333 J / gram
H = 2331000 joules
Heat_3: Total amount of Joules needed.
2331000 + 132300 = 2 463 300 joules
Convert to Megajoules
2 463 300 joules * 1 megajoule / 1000000 = 2.63 megajoules.
The molality of a 0.677 m ethanol ( c 2 h 5 o h ) solution whose density is 0.588 g/ml.
What is molality and molarity?
The number of solvent moles per kilogram is known as molality. Because the mass of the solute and solvent in the solution remains constant, molality is the preferred concentration transfer method.
Molarity, also referred to as molar concentration, is the quantity of a material expressed as moles per litre of solution. Solutions marked with a molar concentration have a capital M. One mole of solvent per litre is present in a 1.0 M solution.
Molar mass (w) of C2H5OH = 46g
Molarity(M) = 0.677M
Density(D) = 0.588g/mol
<u>Molality(m)</u><u> = M/D * (1000 + w*M)</u>
<u>= 1187.2m</u>
To learn more about molality and molarity from the given link below,
brainly.com/question/14770448
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Answer:
A. Soaps react with ions in hard water to create a precipitate.
B. Soaps are both hydrophobic and hydrophilic.
D. Soaps should be weakly alkaline in solution.
Explanation:
A. Hard water contains <u>magnesium and calcium minerals</u> like calcium and magnesium carbonates, sulfates and bicarbonates. As soon as these minerals come in contact with soap their ions like Mg²⁺ & Ca²⁺ form precipitates.
B. Soap are both hydrophilic and hydrophobic. They reason why they exhibit both the properties is really important for their functionality. The hydrophobic part of soap makes interaction with oil/dust particles while the hydrophilic part makes interaction with water. When the cloth is rinsed the dirt/soap particles are removed from the dirty clothes thereby making them clean.
C. Soaps have alkaline pH i.e. more than 7 that is why they have bitter taste.
First by getting moles of salicylic acid:
moles of salicylic acid = molarity * volume
= 0.02 * 0.05 L
= 0.001 mol
then moles of base KOH = molarity * volume
= 0.02 * 0.055L
= 0.0011
when total volume = 0.05 + 0.055 = 0.105 L
[salisalic acid] = moles / total volume
= 0.001 / 0.105
= 0.0095
[KOH] = moles / total volume
= 0.0011 / 0.105
= 0.01
by using H-H equation, we can get the PH:
PH = Pka + ㏒[salt/acid]
by substitution:
PH = 2.97 + ㏒[0.01 / 0.0095]
= 2.99
Answer:
i hope this helps
Magma in the Earth's mantle moves in convection currents. The hot core heats the material above it, causing it to rise toward the crust, where it cools. The heat comes from the intense pressure on the rock, combined with the energy released from natural radioactive decay of elements.
Explanation:
