The correct option is B.
Mendeleev was the one who originated the idea of arranging elements in the periodic table according to their chemical and physical properties. He left spaces in the periodic table and predicted the discovery of those elements that had not been discovered then. One of these elements is Gallium. He predicted that gallium is going to be a metal and he gave the properties that the element will possess. He also predicted that the element gallium will be placed under aluminium in the periodic table.
Answer:
β-hydroxyaldehyde (an aldol) namely 3-Hydroxy butanal.
Explanation:
When acetaldehyde is treated with dil.NaOH it undergoes self condensation as it contains alpha-hydrogen atom in its compound forming β-hydroxyaldehyde (an aldol) namely 3-Hydroxy butanal. This compound upon further heating will eliminate a molecule of water forming aldol condensation product namely Crotonaldehyde Or But-2-en-al. see the diagram attached.
Answer:ABOUT 74 N
Explanation: TOOK THE TEST ON STUDY ISLAND :)
Based on the chemical equation, to balance the equation we use 2 as a coefficients of HCl on left hand side of reaction.
<h3>What is balanced equation?</h3>
Balanced chemical equations are those equation in which each entities are present in same amount on left side as well as on the right side of the chemical reaction.
Given chemical reaction is:
Zn + HCl → ZnCl₂ + H₂
Above reaction is not balanced equation as number of chlorine and hydrogen atoms are not same, so balanced equation will be:
Zn + 2HCl → ZnCl₂ + H₂
Hence we add 2 as a coefficient of HCl to balance the equation.
To know more about balance equation, visit the below link:
brainly.com/question/26694427
Answer:
However, when formal units are used to measure length, the measurement can usually be read from a scale on a ruler or tape, which shows units of a particular size. Unit iteration involves knowledge of repeatedly placing identical tightly packing units so that there are no overlaps or gaps.
Explanation:
