Question

For Numbers 16-19, choose one of the following choices e. covalent bond a. hydrogen bond 16. Which bond is the weakest type of bondi 17. Which type of bond is typically considered the strongest 18. Which bond shares valence electrons? 19. Which bond forms because of the gain or loss of valenc b, ionic bond e electrons that causes atoms to become ions? 20. A gecko lizard uses to stick to surfaces a a sticky slime b. its claws an attractive force at the molecular level between its fingers/toes and surface c. 21. When salt is dissolved in water, the salt is the: a. Solution b. Solute c. Solvent 22. The pH scale ranges from: a. 0-10 b. 0-14 c 1-14 23. A map of eastern North America, showing the pH of rainfall in the various states, indicates that the pH of rain in New York State varies from 4.22 to 4.40. According to these figures, the most acidic rainfall in New York State has a pH of a. 4.22 b. 4.30 c. 4.40 24. Solutions that contain concentrations of H' ions lower than pure water a. b. c; Have pH values below 7.0 Are acids Are bases

Answer 1

A chemical bond is a force between two atoms that holds atoms together in a molecule.

Q.no 16. Weakest bond

Ans. Hydrogen bond is the weakest bond among given three bonds.

Reason. Hydrogen bond belongs to the category of Weak Vanderwaals forces. Hydrogen bond is formed between Hydrogen and an atom more electronegative than Hydrogen like Fluorine, Oxygen, Nitrogen. Hydrogen bond is just a weak force of attraction between partial negative charge on electronegative atom and partial positive charge on Hydrogen atom.

Q.no 17 Strongest bond

Ans. In order to check which bond is stronger, we need to check the bond energy of a particular bond. Higher the bond energy stronger is the bond. But generally Covalent bond is regarded as the strongest bond among given three bonds.

Reason. Covalent bond is formed by the mutual sharing of electrons between two atoms. Mutual sharing is:- atomic orbital of one atom penetrate to the atomic orbital of second atom to make effective overlap leading to the stronger interactions between the two atoms and resulting in formation of stronger bond.

Q.no 18 which bond shares Vanlence electrons

Ans. Most of the chemical bonds use Valence electrons to make bonds but in question there is matter of sharing so the answer is Covalent bond. As we already talked that Covalent bond is formed by the mutual sharing of Valence electrons (outermost shell electrons) between two atoms.

Q.no 19. Bond in which gain and Loss of electrons.

Ans. Ionic bond, which is formed beteen electronegative and electroPositive atoms.

Reason. Ionic bond is formed by the complete transfer of valence electrons from electropostive atom to electronegative atom in order to become stable by achieving nearest noble gas configuration. By transferring electrons there atoms become ions i.e Cation and anion.

Cation . Formed by the atom (electropositive) which donate valence electrons.

Anion. Formed by the atom (electronegative) which accepts valence electrons.

Q.no 20 Gecko lizard

Ans. Gecko lizard uses an attractive force at molecular level between it's fingers/toes and surface for sticking.

Reason. Gecko lizard have bulbous feet in which each finger is covered with hundreds of tiny hairs called Setae. Each seta further splits off into hundreds off very smaller bristles called spatulae. When these spatulae are very close to walls or ceilings there is generation of weak Vanderwaals forces between the feet of Gecko lizard and wall, which sticks lizard to wall effectively .

Q.no 21 Salt dissolved in water.

Ans. When salt is dissolved in water, there is formation of solution. here, salt is Solute. and water is Solvent. Solute is in less amount and solvent is in high amount.

Q.no 22 P_H scale

Ans. PH sacle is the measure of number of Hydrogen ions present in the solution and it helps us to predict whether the given solution is Acidic or Basic. PH scale ranges from 0-14. PH = 0, for stronger acids

PH = 14 for stronger Bases.