Answer:
1.2 × 10⁴ cal
Explanation:
Given data
- Initial temperature: 80 °C
We can calculate the heat released by the water (
) when it cools using the following expression.

where
c is the specific heat capacity of water (1 cal/g.°C)

According to the law of conservation of energy, the sum of the heat released by the water (
) and the heat absorbed by the reaction (
) is zero.

Answer:
When two single single bonds separated by a double bond (e.g C=C-C=C or C=C-C=O in the case of 2-cyclohexenone), the effect of resonance among those there bonds will be observed.
Explanation:
Since the Oxygen atom has higher electronegativity, it will cause the electrons in the resonance bonds 'flow' toward the Oxygen atom, so that the C=C will 'lose' some electron. The signal read for that bond will be different from other alkene structure.
Attachment is the resonance structure of 2-cyclohexene.
Answer:
He is wrong . Most accurate is Buret .
Explanation:
The number of significant figure denotes the level of accuracy of a measurement .
Beaker can measure liquid in mL upto significant figure of 2 . That means it can measure volume in terms of 10 , 20 , 30mL etc . It can not measure 25 mL
accurately . The last figure of 28 mL is read by guess in the question . So it is not an accurate measurement .
Similarly , graduated cylinder can measure liquid upto significant figure of 3 . That means it can measure volume in terms of 11 , 22 , 33 mL etc . It can not measure 25.5 mL accurately . The last figure of 28.3 mL is read by guess in the question . So it is less accurate measurement .
Similarly , buret can measure liquid upto significant figure of 4 . That means it can measure volume in terms of 11.2 , 22.3 , 33.5 mL etc . It can not measure 25.53 mL accurately . The last figure of 28.32 mL is read by guess in the question . So it is most accurate among all the three instrument because it can measure accurately mL upto one tenth of it .
Answer:
The volume of the piece of iron is 5.18dL.
Explanation:
The density (ρ) is equal to the mass (m) divided the volume (V).

If we rearrange it, we have:

To express the volume in dL we will need the following relations:
- 1 dL = 0.1 L
- 1 kg = 10³ g
- 1 cm³ = 1 mL
- 1mL = 10⁻³L
Then,

Finally,

Answer:
The molecular formula of the given compound is C6H12O6, which is also called Glucose.
Explanation:
The molar mass of glucose is 180.18.