Answer:
The correct answer is "5217 Cal".
Explanation:
The given values are:
Specific heat,
c = 3.76 cal/g°C
Mass,
m = 25.0 g
Initial temperature,
T₁ = 21.5°C
Final temperature,
T₂ = 77.0°C
Now,
The heat energy will be:
⇒ 
On substituting the given values, we get
⇒ 
⇒ 
⇒ 
Answer:
The term matter refers to anything that occupies space and has mass—in other words, the “stuff” that the universe is made of. All matter is made up of substances called elements, which have specific chemical and physical properties and cannot be broken down into other substances through ordinary chemical reactions.
0.81 moles
Explanation:
cobalt chloride when dissolved in water dissociate into cobalt and chloride ions as shown;
CoCl₂ (s) → [Co²⁺](aq) + 2[Cl⁻] (aq)
The mole ratio between CoCl₂ and [Co²⁺] is 1 ; 1 while the mole ratio between CoCl₂ and [Cl⁻] is 1 : 2
Therefore; 0.27 moles of CoCl₂ will form;
(1 * 0.27) = 0.27 moles of [Co²⁺] ions
(2 * 0.27) = 0.54 moles of [Cl⁻] ions
Total moles of dissociated ions are;
0.27 + 0.54
= 0.81 moles
Answer:
A. True
B. False
C. False
D. True
E. False
Explanation:
A. The proximal histidine covalently binds iron.
This statement is true because the proximal histidine is covalently bonded to the fifth coordination position of iron in myoglobin
B. The distal histidine covalently binds oxygen.
This statement is false because the distal histidine interacts with the oxygen covalently bonded to the sixty coordination position of iron by means of a hydrogen bond not a covalent bond.
C. The distal histidine binds iron
This statement is false because the distal histidine is not bonded to iron but to oxygen but stabilizes the oxygen bonded to iron
D. Free heme binds CO with the Fe, C and O atoms in a linear array.
This statement is true because free heme has more affinity for CO than O2 as it has the least steric hindrance when the Fe, C, and O atoms lie in a straight line. On the other hand, when O2 binds to free heme, the axis of the oxygen molecule is positioned at an angle to the Fe-O bond thereby producing significant steric hindrance.
E. The iron in heme binds the oxygen atom of CO.
This statement is false because the iron in heme binds to the carbon atom, C, of CO rather than to oxygen atom.
Answer:
(d) soap.
Explanation:
A soap is obtained by alkaline hydrolysis of a fat to yield the soap and glycerol. This process is known as saponification.
A soap solution is usually basic. Since phenolphthalein turns pink in an alkaline solution, then when phenolphthalein is added to a soap solution, the solution soon turns pink because it is alkaline in nature.
As a matter of fact, a soap sometimes has almost the pH of baking soda!
