This is a reduction reaction as the oxide(oxygen) is taken away from the metal =]
Answer: <u> two hydrogen atoms and one oxygen</u> atom are removed during dehydration synthesis.
Hope this helps!
Answer is (4) - Pb.
According to the reactivity series of elements
- the elements which are above the hydrogen are more reactive than hydrogen.
- the elements which are below the hydrogen are less reactive than hydrogen.
Among the given choices, only Pb is placed above the hydrogen in the reactivity series and rest are below the hydrogen.
Hence, Pb is more active than hydrogen.
Answer: There are five significant figures in 865,010.
Explanation:
When a degree of accuracy is stated by each digit present in a mathematical figure then it is called a significant figure.
Rules for counting significant figures is as follows.
- Any non-zero digits and zeros present between a non-zero figure are counted. For example, 3580009 has seven significant figures.
- Trailing zeros are counted in a non-zero figure. For example, 0.00250 has three significant figures.
- Leading zeros are not counted. For example, 0.0025 has two significant figures.
So, in the given figure 865010 has five significant figures and the trailing zero will not be counted.
Thus, we can conclude that there are five significant figures in 865,010.