Answer:
I am sure that the C one is correct
We have to complete all the given reactions.
1. Fe(s) + CuCl₂ → Cu + FeCl₂
2. Cu(s) + FeCl₂(aq) → NR (no reaction takes place)
3. K(s) + NiBr2(aq) → NR (no reaction takes place)
4. Ni(s) + KBr(aq) → K + NiBr₂
5. Zn(s) + Ca(NO₃)₂(aq) → NR (no reaction)
6. Ca(s) + Zn(NO₃)₂(aq) → Zn(s) + Ca(NO₃)₂(aq)
Answer: A chemical process must occur and then changes between the state of the reactants and the state of the products can be determined
Explanation: Enthalpy represents the sum of the energy of the system with the product of the pressure and volume of that system. As a thermodynamic property, it expresses the ability to release heat from the system. In fact, enthalpy tells us how much heat and work has changed during the chemical reaction under constant pressure. When measuring, measurements of the difference in enthalpy between the two states of the system is performed, before and after the chemical reaction, since total enthalpy can not be measured. This measurement of the enthalpy change can tell us, for example, whether the heat was released from the system during the reaction, or the system absorbed the heat.
Answer:
38.3958 °C
Explanation:
As,
1 gram of carbohydrates on burning gives 4 kilocalories of energy
1 gram of protein on burning gives 4 kilocalories of energy
1 gram of fat on burning gives 9 kilocalories of energy
Thus,
27 g of fat on burning gives 9*27 = 243 kilocalories of energy
20 g of protein on burning gives 4*20 = 80 kilocalories of energy
48 gram of carbohydrates on burning gives 4*48 = 192 kilocalories of energy
Total energy = 515 kilocalories
Using,
Given: Volume of water = 23 L = 23×10⁻³ m³
Density of water= 1000 kg/m³
So, mass of the water:
Mass of water = 23 kg
Initial temperature = 16°C
Specific heat of water = 0.9998 kcal/kg°C
Solving for final temperature as:
<u>Final temperature = 38.3958 °C </u>
