Explanation:
total heat = Heat required to convert 2 kg of ice to 2 kg of water at 0 °C + Heat required to convert 2 kg of water at 0 °C to 2 kg of water at 20 °C.
Heat=mhfg+mCpΔT
Here, m ( mass of ice) = 2 kg
hfg (latent heat of fusion of ice) = 334 KJ
Cp of water (specific heat) = 4.187 KJ/Kg-K
ΔT(Temperature difference) = 20 °C
Therefore, Heat required = 2 x 334 + 2 x 4.187 x (20 - 0 )
Heat reqd= 835.48 KJ
Therefore, to melt 2 kg of ice 835.48 KJ of heat is required.
Answer:
The correct answer is thermophiles.
Explanation:
Thermus aquaticus are heat resistant bacteria because these bacteria can survive under adverse environmental conditions like high temperature.
These bacteria belong to one of the most heat-loving groups of extremophiles that are thermophiles. Thermophiles are present in volcanic soil, geysers and around deep-sea vents where the temperature is extremely high.
Thermus aquaticus bacteria is used to manufacture an enzyme called Taq DNA polymerase, which is heat resistant and also an important factor in molecular biology.
Answer:
chemical change
Explanation:
chemical change requires energy in the form of heat or electricity.
Dipyrithione is a chemical with formula, C₁₀H₈N₂O₂S₂. This means that each molecule of the substance has two (2) atoms of nitrogen. By using the dimensional analysis and Avogadro's number, equal to 6.022 x 10²³, we calculate for the answer as shown below.
n = (8.2 x 10²⁴ atoms N)(1 molecule dipyrithione/ 2 atoms of N)(1 mole dipyrithione/ 6.022 x 10²³ molecules dipyrithione)
Simplifying,
n = 6.8 moles dipyrithione
<em>ANSWER: 6.8 moles</em>
Answer:
C. Solid
Explanation:
It's most about the kinetic energy, when molecules have the least amount of room to move around, they have the least amount of energy.
For example if you think about gas and how spread out the molecules are in order to evaporate, there it the highest amount of energy there.
