<h2>Answer:</h2>
A pure metal has specific properties. Sometimes we need that metal but with modified properties. So for the modification of properties we make alloys.
<h3>Explanation;</h3>
- An alloy is a mixture of two elements, one of which is a metal.
- Alloys often have properties that are different to the metals they contain.
- This makes them more useful than the pure metals alone.
- For example, alloys are often harder than the metal they contain.
Chemical,when you light a match stick, you are starting a chain reaction of the substance chemical formula, making it a chemical change
Answer:
Being a weak acid and a strong base, where it is diluted in a neutral medium such as water, the basic medium predominates, almost alkaline pH.
Explanation:
The acidity of the solution, being weak, means that its pH is not so low, therefore it will be easier to reach the values of 7 or 7 where alkalinity or basity is indicated.
ANSWER
EXPLANATION
Given that
The energy released by the system is 12.4J
Work done on the surrounding is 4.2J
Follow the steps below to find the change in energy
In the given data, energy is said to be released to the surroundings
Recall, that exothermic reaction is a type of reaction in which heat is released to the surroundings. Hence, change in enthalpy is negative
Step 1; Write the formula for calculating change in energy

Since heat is released to the surrounding, then q = -12J
Recall, that work done by the system on the surroundings is always negative
Hence, w = -4.2J
Step 2; Substitute the given data into the formula in step 1

Therefore, the change i
Answer:
C. 30 kJ
Explanation:
Hello there!
In this case, in agreement to the thermodynamic definition of the Gibbs free energy, in terms of enthalpy of entropy:

It is possible to calculate the required G by plugging in the given entropy and enthalpy as shown below:

Therefore, the answer is C. 30 kJ
.
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