Answer:
527.184 J of heat is removed from a 21 g water sample if it is cooled from 34.0 ° C to 28.0 ° C.
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
When the heat added or removed from a substance causes a change in temperature in it, this heat is called sensible heat.
In other words, the sensible heat of a body is the amount of heat received or transferred by a body when it undergoes a change in temperature without there being a change in physical state (solid, liquid or gaseous). The equation that allows to calculate this heat exchange is:
Q = c * m * ΔT
Where Q is the heat exchanged by a body of mass m, constituted by a substance of specific heat c and where ΔT=Tfinal-Tinitial is the change in temperature.
In this case:
- c= 4.184

- m=21 g
- ΔT=Tfinal-Tinitial=28 °C - 34 °C=-6 °C
Replacing:
Q= 4.184
* 21 g* (-6 C)
Q= - 527.184 J
To lower the temperature, heat has to be given, for that the final temperature must be lower than the initial temperature; and it receives the name of transferred heat and has a negative value, as in this case.
<u><em>
527.184 J of heat is removed from a 21 g water sample if it is cooled from 34.0 ° C to 28.0 ° C.</em></u>
The reaction which shows oxidation and reduction simultaneously is C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l).
<h3>What are redox reactions?</h3>
Those reaction in which oxidation as well as reduction of substances takes place simultaneously will known as redox reactions.
- SO₂(g) + H₂O(l) → H₂SO₃(aq)
- CaCO₃(aq) → CaO(s) + CO₂(g)
- Ca(OH)₂(s) + H₂CO₃(l) CaCO₃(aq) + 2H₂O(l)
Above reaction are not the redox reactions as in these reaction oxidation and reduction simultaneously not takes place.
- C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l)
In the above reaction reduction of oxygen takes place as its oxidation state changes from 0 to -2, and at the same time oxidation of carbon takes place as its oxidation state changes from 0 to +4.
Hence correct option is (4).
To know more about redox reactions, visit the below link:
brainly.com/question/7935462
It’s 1 or 3 sorry if this is wrong
Answer:
The glycosylation reaction or glycoside formation is an organic reaction in which the hemiacetal group of cyclists ketoses or aldoses turns into acetals, named glycosides. Reaction in the attached picture.
Explanation:
Carbohydrates can be found in an open-chain form or a cyclic form. For the second one, the carbonyl group of the aldehyde could react with the alcohol group of the molecule to form the cycle. As shown in the attached picture, the alcohol group of this cyclic form could react with an alcohol (like methanol) in acidic conditions to form an acetal. These compounds are stable at neutral and acidic conditions, but they hydrolyze at basic conditions. This reaction produces both acetals anomers (α and β) because the attack of the nucleophile (alcohol) could be from both sides. However, the most stable anomer will predominate.
Hi there!
p = e-3
s = f-1
f = i-7
d = g-5
Hope that helps!
Brady