Answer:
3. turns pink and is basic
Explanation:
Phenolphthalein is a pH indicator that remains colorless in acidic solutions, but in basic solutions it turns pink at a pH equal to 10.
Phenolphthalein is a weak acid that loses H+ cations in solution. The phenolphthalein molecule is colorless, while the phenolphthalein-derived anion is pink. When a base is added, phenolphthalein loses H+, forming the anion and causing it to turn pink. The color change cannot be explained only on the basis of deprotonation, a structural change occurs with the appearance of a ketoenolic tautomerism.
Answer:
60 cm³ of water
Explanation:
We'll begin by calculating the volume of the diluted solution. This can be obtained as follow:
Concentration of stock solution (C₁) = 17 M
Volume of stock solution (V₁) = 25 cm³
Concentration of diluted solution (C₂) = 5 M
Volume of diluted solution (V₂) =?
C₁V₁ = C₂V₂
17 × 25 = 5 × V₂
425 = 5 × V₂
Divide both side by 5
V₂ = 425 / 5
V₂ = 85 cm³
Thus, the volume of the diluted solution is 85 cm³
Finally, we shall determine the volume of water needed to dilute the solution. This can be obtained as follow:
Volume of stock solution (V₁) = 25 cm³
Volume of diluted solution (V₂) = 85 cm³
Volume of water =?
Volume of water = V₂ – V₁
Volume of water = 85 – 25
Volume of water = 60 cm³
Therefore, 60 cm³ of water is needed to dilute the solution.
Answer:
SiH
Explanation:
The symbol for Silicon is Si, and the symbol for Hydrogen is H. There is no need for extra characters in the name.
Valence Electron is the outermost electrons, family(Alkali) 1 has 1 valence electrons and family(Alkaline) 2 has 2 valence electrons.
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