It will take 1.11 min to heat the sample to its melting point.
Melting point = - 20°C
Boiling point = 85°C
∆H of fusion = 180 J/g
∆H of vap = 500 J/g
C(solid) = 1.0 J/g °C
C(liquid) = 2.5 J/g °C
C(gas) = 0.5 J/g °C
Mass of sample = 25 g
Initial temperature = - 40°C
Final temperature = 100°C
Rate of heating = 450 J/min
Specific heat capacity formula:- q = m ×C×∆T
Here, q = heat energy
m = mass
C = specific heat
∆T = temperature change
Melting point = - 20°C
C(solid) = 1.0 J/g °C
∆T = final temperature - initial temperature = -20 - (-40) = 20
Put these value in Specific heat capacity formula
q = m ×C×∆T
q = 25×1.0×20
=500J
The Rate of heating = 450 J/min
i.e. 450J = 1min
so, 500J = 1.11min
1.11 minutes does it take to heat the sample to its melting point.
The specific heat capacity is defined as the amount of heat absorbed in line with unit mass of the material whilst its temperature increases 1 °C.
Learn more about specific heat capacity here:- brainly.com/question/26866234
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Answer: Option (b) is the correct answer.
Explanation:
A synthesis reaction is the reaction in which two compounds or atoms combine together to result in the formation of a single compound.
For example, 
Thus, here CaO and 
combine together to result in the formation of calcium carbonate compound. Therefore, it is a synthesis reaction.
Therefore, we can conclude that the most likely products of Cao + co2 → CaCO3 reaction.
There are 13 atoms in the product
<h3>Further explanation</h3>
Given
Reaction
H2SO4 + 2KOH --> K2SO4 + 2H2O
Required
The number of atoms
Solution
In a chemical equation, there are reactants on the left and products on the right
Reactants : H2SO4 + 2KOH
Products : K2SO4 + 2H2O
The number of atoms is determined by their reaction coefficient and the subscript of the atoms in the compound
K2SO4 (coefficient = 1) :
K = 2 atoms
S = 1 atom
O = 4 atoms
Total atoms = 7 atoms
2H2O(coefficient = 2) :
H = 2 x 2 = 4 atoms
O = 2 x 1 = 2 atoms
Total atoms = 6 atoms
Total = 13 atoms
Answer:
Ni
Explanation:
An active metal is a highly reactive metal. Active metals are found high up in the activity series.
Active metals react with other metals that are lower than them in the activity thereby displacing the lower metals from a solution of their salts. This is what may have happened in the other two reactions.
Ni is the most active metal listed in the question since it can react a compounds with Pb(NO3)2(aq) to liberate Pb metal.
