Answer:
A carbohydrate is a compound composed of molecules of carbon (C), hydrogen (H), and oxygen (O) such that its general chemical formula is 
.
Biochemical functions of carbohydrates: Carbohydrates provide Stored Energy, Carbohydrates help to preserve Muscle and promote digestive health and Carbohydrates build macromolecules
Explanation:
A carbohydrate is a compound composed of molecules of carbon (C), hydrogen (H), and oxygen (O) such that its general chemical formula is .
Biochemical functions of carbohydrates:
1. Carbohydrates provide Stored Energy.
2. Carbohydrates help to preserve Muscle and promote digestive health.
3. Carbohydrates build macromolecules
Answer: Burning changes the chemical make up of an object.
Explanation:
A chemical change can be defined as a change in the substance when it combines with other kind of substance to form a new substance. A chemical change can also occur when a substance is broken down into two or more products. These changes cannot be reversed. These changes affect the physical make up of an object. For example, burning as when an object is burned it cannot be transformed into its original form. A wood if burned can be converted into ash, water and carbon dioxide cannot regain its original form after burning so burning brings about chemical change in an object.
Answer:
11.31g NaClO₂
Explanation:
<em> Is given 250mL of a 1.60M chlorous acid HClO2 solution. Ka is 1.110x10⁻². What mass of NaClO₂ should the student dissolve in the HClO2 solution to turn it into a buffer with pH =1.45? </em>
It is possible to answer this question using Henderson-Hasselbalch equation:
pH = pKa + log₁₀ [A⁻] / [HA]
<em>Where pKa is -log Ka = 1.9547; [A⁻] is the concentration of the conjugate base (NaClO₂), [HA] the concentration of the weak acid</em>
You can change the concentration of the substance if you write the moles of the substances:
[Moles HClO₂] = 250mL = 0.25L×(1.60mol /L) = <em>0.40 moles HClO₂</em>
Replacing in H-H expression, as the pH you want is 1.45:
1.45 = 1.9547 + log₁₀ [Moles NaClO₂] / [0.40 moles HClO₂]
-0.5047 = log₁₀ [Moles NaClO₂] / [0.40 moles HClO₂]
<em>0.3128 = </em>[Moles NaClO₂] / [0.40 moles HClO₂]
0.1251 = Moles NaClO₂
As molar mass of NaClO₂ is 90.44g/mol, mass of 0.1251 moles of NaClO₂ is:
0.1251 moles NaClO₂ ₓ (90.44g / mol) =
<h3>11.31g NaClO₂</h3>
Answer:
D. Surface tension.
Explanation:
Surface tension is defined as the energy required to increase the surface area of a liquid by a unit amount.
The surface tension of a liquid results from an imbalance of intermolecular attractive forces, the cohesive forces between molecules:
A molecule in a liquid experiences cohesive forces with other molecules in all directions while molecules at the surface of a liquid experiences only net inward cohesive forces.
