Answer:
two
Explanation:
The number of significant figures needed in the answer is 2.
This is because when finding the products of two numbers, the result is as accurate as the least number of significant figures of the numbers being multiplied.
Here the numbers being multiplied are;
1.31m
6.5m
1.31m has 3 significant figures
6.5m has 2 significant figures.
So, the product will have 2 significant figures
In the first situation: the mechanism of covection is the main form of heat transfer when warm air from a heater moves around and upward.
In the case of the metal pan the mechanism of heat transfer is conduction.
In the case of sunburn the mechanism is radiation.
In the case of an ice cube melting in a hand, conduction is the most important mechanism.
Answer:
Explanation:
Hello,
In this case, since the chemical reaction is:
We can see that hydrochloric acid and magnesium hydroxide are in a 2:1 mole ratio, which means that the neutralization point, we can write:
In such a way, the moles of magnesium hydroxide (molar mass 58.3 g/mol) in 500 mg are:
Next, since the pH of hydrochloric acid is 1.25, the concentration of H⁺ as well as the acid (strong acid) is:
![[H^+]=[HCl]=10^{-pH}=10^{-1.25}=0.0562M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D%5BHCl%5D%3D10%5E%7B-pH%7D%3D10%5E%7B-1.25%7D%3D0.0562M)
Then, since the concentration and the volume define the moles, we can write:
![[HCl]*V_{HCl}=2*n_{Mg(OH)_2}](https://tex.z-dn.net/?f=%5BHCl%5D%2AV_%7BHCl%7D%3D2%2An_%7BMg%28OH%29_2%7D)
Therefore, the neutralized volume turns out:
Best regards.
