Answer:
25.3 g of KNO₃ contain 0.25 moles.
Explanation:
Given data:
Number of moles of KNO₃ = ?
Mass of KNO₃ = 25.3 g
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass of KNO₃:
KNO₃ = 39 + 14+ 16×3
KNO₃ = 101 g/mol
Now we will put the values in formula.
Number of moles = 25.3 g/ 101 g/mol
Number of moles = 0.25 mol
Thus, 25.3 g of KNO₃ contain 0.25 moles.
The change in internal energy of a system is 1648.45 J.
First we convert calories into joule :-
From question, values are given q = 0.615 kJ
q = 615 J
w = 0.247 kcal
w = 247 Cal = 247 × 4.184 J
w = 1033.45 J
Formula of change in internal energy, ΔE = q + w
Here, the system absorbs heat from surroundings, so q is positive
Now, put the values of q and w in the formula,
ΔE = q + w
ΔE = 615 + 1033.45 J
ΔE = 1648.45 J
Internal energy is the sum of ability power of the gadget and the machine's kinetic strength. The alternate in internal energy (ΔU) of a response is equal to the heat gained or lost (enthalpy trade) in a reaction whilst the reaction is administered at steady pressure. Inside the study of thermodynamics, a usually perfect gasoline is taken into consideration as a running substance. The molecules of an ideal gasoline are mere mass points that exert no force on each other.
The SI derived unit used to degree strength or paintings. One joule is identical to the electricity used to accelerate a body with a mass of 1 kilogram using one newton of force over a distance of one meter. One joule is also equal to one watt-second.
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Answer:
electromagnetic waves
Explanation:
Radiation is the transfer of heat energy through space. Most of them are sent through electromagnetic waves.
Single replacement or single displacement reactions
Explanation:
In a single replacement or displacement reaction, the activity series is useful in predicting whether the reaction will take place or not.
- In this reaction type, one substance is replacing another.
C + DE → CD + E
- The relative positions of the two elements in the activity series provides the driving force for the single replacement reaction.
- An element high up in the series will displace one that is lower in the series because it is more reactive.
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Chemical reactions brainly.com/question/3953793
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Answer:
There are 4 tryptophans in the protein.
Explanation:
According to question, protein contains one tyrosine residue and say x number of tryptophans.
Concentration of protein solution = 1.0 micromolar = 
Molar absorptivity of a protein solution : 


Length of the cuvette = l = 1.0 cm
Absorbance of protein solution at 280 nm = A = 0.024
( Beer-Lambert's law)

Solving for x :
x = 4
There are 4 tryptophans in the protein.