Methanoic acid has a molecular formula of HCOOH, when form an ester it's HCOO-, so the rest of the ester is -C4H9, a saturated 4 carbon chain. As shown in the attached diagram, there are 4 structural isomers, and the third isomer has 2 stereoisomers. So the answers is D:5.

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The normality that would be calculated will be to high because the change in volume will be greater than the actual change in volume. if the buret tip is not filled when reading the initial volume, the actual volume should be lesser with that reading. so if you will you the higher reading the change in volume or the volume you use in titration will be higher than the actual
A Nonrewnewable source is hard to get back from its source, while a renewable source is easy to get back from its source.
Example:
Nonrenewable: crude oil, oil, coal, fossil fuels, etc.
Renewable: sunlight, wind, biomass, rain, tides, waves and geothermal heat, etc.
Answer:
(NH₄)₂(SO₄)+H₂O⇒(NH₄)₂O+H₂(SO₄)
Explanation:
(NH₄)⁺(SO₄)²⁻+H₂O⇒(NH₄)⁺O²⁻+H₂(SO₄)²⁻
(NH₄)₂(SO₄)+H₂O⇒(NH₄)₂O+H₂(SO₄)