Answer:
700 calories
Explanation:
Using the formula below:
Q = m × c × ∆T
Where;
Q = amount of heat required (calories)
m = mass of substance (g)
c = specific heat of substance (cal/g°C)
∆T = change in temperature (°C)
According to this question, the following information was provided;
Q = ?
m = 20g
c = 1.0 cal/g °C
∆T = 40°C - 5°C = 35°C
Using the formula; Q = m × c × ∆T
Q = 20 × 1 × 35
Q = 700 calories
Hence, 700 cal of heat energy is needed to raise 20 g of H2O from 5°C to 40°C.
Answer:

Explanation:
Hello,
In this case, for the given reactants we identify the following chemical reaction:

Thus, we evidence a 1:1 molar ratio between KOH and HCl, therefore, for the complete neutralization we have equal number of moles, that in terms of molarities and volumes become:

Hence, we compute the volume of HCl as shown below:

Best regards.
During the reaction of glucose and fructose with excess phenylhydrazine to form osazone, only the C-1andC-2 atoms of glucose and fructose participate in the reaction. The rest of the molecule remains intact. Hence, glucose and fructose produce the same osazone.
The chemical compound sodium sulfide has the formula Na2S. It is written as
. It has a crystalline state. Na is followed by a two or 2. this indicates that the molecule has two of the specified element's atoms.
There is just one of these because there is no number following the S.
In all, this molecule consists of one sulfur atom and two sodium atoms.
A compound's chemical formula, which uses symbols for combining atoms, reveals the composition of the complex. We require the valency of the combining parts in order to write the formula.
The sodium sulfide chemical formula must be written down. So sodium and sulfur make up the two elements in the chemical. Sodium has a valency of +1, while sulfur has a +2.
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