D. Sodium and Chlorine
Sodium has 1 electron and Chlorine has 7 electrons. For a compound to be stable, they must have 8 electrons. NaCl = 8 electrons
Fun Fact- You eat NaCl everyday. It's table salt which you put in food.
It covers your body with cloth and acts as a protectant against harsh conditions. Its almost like a portable blanket!
Answer:
Explanation:
The total energy or intrinsic energy of a system is called the enthalpy. In thermochemistry, we have two types of enthalpy changes which are:
- Exothermic changes
- Endothermic changes
For the freezing of water, the enthalpy change is an exothermic one. Exothermic changes are designated as negative. In this chemical change, heat is liberated to the surroundings and this leaves the environment at a much higher temperature. In freezing, the enviroment gains more heat as the material begins to cool to lower temperature.
Entropy is the degree of randomness or disorderliness of a system. When a phase change occurs from liquid to solid, freezing takes place. Such a change increases the orderliness of a system and entropy diminishes. Here, entropy is negative.
The free energy is a measure of the energy a system that does useful work. Free energy depends on enthalpy, entropy and temperature of a system. For phase changes such as freezing of water, the value of free energy change is 0.
For this process, an increases in temperature makes it non-spontaneous. Increasing temperature would alter the course of the reaction and makes it exothermic. For entropy, increasing temperature would increase entropy and therefore, the reaction would not be feasible.
Temperature would mostly affect the free energy. An increase in temperature would increase the value of entropy change and the reaction would not be spontaneous. With falling temperature value, the reaction becomes more spontaneous and favored.
Answer:
0.031moles
Explanation:
ok so it would help if I knew the marks but 1 mole = 1000L so if the volume was 31L then if you convert you will get that answer
Answer:
Wind energy
An ideal source of energy needs to be reliable, cost effective, safe and must lead to almost zero adverse environmental impact.
Wind energy is energy obtained from air moving at high velocity. This energy is harvested using windmills which convert mechanical energy to electrical energy.
Wind is inexpensive because it occurs naturally. However, a large expanse of land is required in order to mount sufficient number of windmills that will generate enough electrical energy for practical purposes.
This method of electricity generation is safe and does not lead to any environmental hazard unlike the burning of fossil fuels, use of nuclear energy or loss of habitat due to hydroelectric power generation.
Explanation:
