What element is used to disinfect swimming pools?

Correct Answer: Sr

Explanation:

We know that, elements in the same group of the periodic table have similar characteristics. Here magnesium and strontium are the same 2nd group elements and have same behavior. 

Therefore, strontium behaves same as magnesium. 

Correct Answer: NaCl (Aq)

Explanation:

Mixtures are combination of two or more substances physically which can be separated in to the original.

Matter can be breakdown into two categories. 

1) Pure substances 

2) Mixtures

 

Here in the given options, options A, B, C are pure substances as they are indicated as S & L in brackets. Option D) is an aqueous solution, that can be dissolved in water.

Correct Answer: Oxygen

Explanation:

Oxygen is the final electron acceptor of cellular respiration.

Correct Answer: a nonpolar molecule with polar bonds

Explanation:

The four bonds of carbon tetrachloride (CCl4) are polar, but the molecule is nonpolar because the bond polarity is cancelled by the symmetric tetrahedral shape. Hence, making the net dipole as zero and molecule as non-polar.

 

When other atoms substitute for some of the Cl atoms, the symmetry is broken and the molecule becomes polar.

Correct Answer: Emulsion

Explanation:

Milk is an emulsion of oil in water (o/w).

Emulsion: A suspension of droplets of one liquid in another.

Constituents of milk :

The principal constituents of milk are water, fat, proteins, lactose (milk sugar) and minerals (salts). Milk also contains trace amounts of other substances such as pigments, enzymes, vitamins, phospholipids (substances with fatlike properties), and gases.

Correct Answer: ATP to ADP

Correct Answer: H-F

Explanation:

Ionic character depends on the electronegativity difference between the bonding elements. The greatest the elctronegativity diffference the greatest the ionic character.

Here in the given options, H-F has has the greatest ionic character. The electronegativity of Hydrogen is 2.1 and that of Fluorine is 4. Now the electronegativity difference is 4 - 2.1 = 1.9.

 

Correct Answer: Poly carbonates

Correct Answer: Oxygen

Explanation:

Electronegativity measures an element's ability to form chemical bonds. Helium is the most electronegative element followed by Fluorine.

 

Here in the given options, Oxygen is the most electronegative element. Fluorine is followed by Oxygen, Chlorine and Nitrogen is the most electronegative elements list.

Correct Answer: Skimming

Explanation:

Skimming is the removal of any material or particles that are floating on the surface. Hence, Removal of oil and grease from sewage - waste water is called as skimming.