Answer:
Curd, lemon juice, orange juice and vinegar taste sour. These substances taste sour because they contain acids. The chemical nature of such substances is acidic. The word acid comes from the Latin word acere which means sour.
They don't change what the substance really is unlike chemical change. They chemical formula of the substance stays the same even though the substance can go under shape change.
Answer:
The average velocity of the airplane for this trip is 1684.21 km/h
Explanation:
Average velocity is the rate of change of displacement with time. That is,
Average velocity =
= Δx / Δt = 
Now we will calculate the time taken by the airplane for the first motion before it encounters a wind.
From,
Velocity = 
Time = 
Therefore, Time = 
Time = 2.1h
This is the time taken before the airplane encounters a wind.
Hence, t1 = 2.1h
Now, For the time taken by the airplane when it encounters a wind
Also from,
Velocity = 
Time = 
Therefore, Time = 
Time = 1.625h
Hence, t2 = 1.625h
Now, to calculate the average velocity
Average velocity = 
x1= 2100, x2= 1300, t1= 2.1h and t2= 1.625h
Hence, Average velocity = 
Average velocity = 1684.21 km/h
Answer:
pH 4
Explanation:
Firstly, we define pH as the negative logarithm to base 10 of the concentration of hydrogen ions.
Mathematically, we express this as:
pH = -log[H+]
Now let’s us calculate the concentration of hydrogen in each of the pH
For pH 4, we have:
4 = -log[H+]
[H+] = -Antilog(4)
[H+] = 0.0001M
For pH 5,
[H+] = -Antilog(5)
[H+] = 0.00001M
We can see that 0.0001 is greater than 0.00001 and thus it has a greater concentration of hydrogen ions