948 or 9.48 x 10^2
There are two sets of rules for significant figures
• One set for addition and subtraction
• Another set for multiplication and division
You used the set for multiplication and division.
This problem involves addition and subtraction, and the rule is
The number of places after the decimal point in the answer must be <em>no greater than the number of decimal places in every term</em> in the sum.
Thus, we have
78.9
+890.43
-21.
= 948.33
The "21" term has the fewest digits after the decimal point (none), so the answer must have no digits after the decimal point.
To the correct answer is 948 = 9.48 x 10^2. It has three significant figures.
The H+ concentration that would best describe a basic solution would be the one having values less than 10^-7. The pH of a solution is related to H+ concentration by pH = -log[H+]. Therefore, as the concentration of H+ decreases the alkalinity would rise.
In a redox chemical reaction, one species gets reduced and another gets oxidized. Manganese element is reduced in this reaction.
<h3>What is oxidized and reduced?</h3>
In a redox reaction, the increase or decrease in the oxidation number and electrons results in the reduction and oxidation of the chemical species. The oxidation and reduction occur simultaneously in a reaction.
The oxidation number of Mn in permanganate ion was +8 on the left side and decreased to +4 on the right side of the equation. Potassium permanganate is an oxidizing agent that has reduced the manganese ion of the permanganate ion.
Therefore, manganese is reduced.
Learn more about reduction and oxidation here:
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NO₂ is a brown gas while N₂O₄ is colorless. If heating causes a brown color to persist, then this means that heating causes the reaction to shift backwards and produce NO₂. Therefore, the reaction must be exothermic.
Answer:
It helps the body remove heat through sweating.
Explanation:
When the weather is hot, the body tries to keep cool by sweating. The high specific heat capacity means that the body doesn't have to lose much water to stay cool.
The high specific heat capacity of water doesn’t heat the body, but it slows down the rate of heat loss when the weather is cool.
B is wrong. The body uses glucose, not water, as an energy source.
C is wrong. The high specific heat capacity of water is not connected with the body's ability to store it.
D is wrong. The high specific heat capacity of water doesn't heat the body, but it slows the rate at which it cools.