Answer:
THE HEAT NEEDED TO CHANGE 3KG OF WATER FROM 10 C TO 80 C IS 877.8kJ OR 877,800 J.
Explanation:
Mass = 3.0 kg = 3 * 1000 = 3000 g
Initial temperature = 10 C
Final temperature = 80 C
Change in temperature = 80 - 10 = 70 C
Specific heat of water = 4.18 J/g C
Heat needed = unknown
Heat is the amount of energy in joules needed to change a gram of water by 1 C.
Heat = mass * specific heat * change in temperature
Heat = 3000 g * 4.18 J/g C * 70 C
Heat = 877 800 Joules
Heat = 877.8 kJ.
The heat needed to change 3 kg mass of water from 10 C to 80 C is 877,800 J or 877.8 kJ.
Answer:
Approximately .
Explanation:
Balanced equation for this reaction:
.
Look up the relative atomic mass of elements in the limiting reactant, , as well as those in the product of interest, :
Calculate the formula mass for both the limiting reactant and the product of interest:
.
.
Calculate the quantity of the limiting reactant () available to this reaction:
.
Refer to the balanced equation for this reaction. The coefficients of the limiting reactant () and the product () are both . Thus:
.
In other words, for every of formula units that are consumed, of formula units would (in theory) be produced. Thus, calculate the theoretical yield of in this experiment:
.
Calculate the theoretical yield of this experiment in terms of the mass of expected to be produced:
.
Given that the actual yield in this question (in terms of the mass of ) is , calculate the percentage yield of this experiment:
.
Answer:
561 g P₂O₃
Explanation:
To find the mass of P₂O₃, you need to (1) convert moles H₃PO₃ to moles P₂O₃ (via mole-to-mole ratio from equation coefficients) and then (2) convert moles P₂O₃ to grams P₂O₃ (via molar mass). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to match the amount of sig figs in the given value.
Atomic Mass (P): 30.974 g/mol
Atomic Mass (O): 15.998 g/mol
Molar Mass (P₂O₃): 2(30.974 g/mol) + 3(15.998 g/mol)
Molar Mass (P₂O₃): 109.942 g/mol
1 P₂O₃ + 3 H₂O -----> 2 H₃PO₃
10.2 moles H₃PO₃ 1 mole P₂O₃ 109.942 g
---------------------------- x -------------------------- x ------------------- = 561 g P₂O₃
2 moles H₃PO₃ 1 mole
Evaporation must happen before they can form, because clouds are condensing, which means that they first have to evaporate, then they will condense, and form clouds.
Answer:
D:Nuclear fusion plays an important role in making elements that are heavier than helium
Explanation:
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