Answer:
For O: atomic number = 8 # neutrons = 8
For Al: atomic mass = 27, # electrons = 13
Answer:
b. 54.9%
Explanation:
An emerald gemstone has the formula Be₃Al₂Si₁₆O₁₈. We can find the mass of each element in 1 mole of Be₃Al₂Si₁₆O₁₈ by multiplying the molar mass of the element by its atomicity.
Be: 3 × 9.01 g = 27.03 g
Al: 2 × 26.98 g = 53.96 g
Si: 16 × 28.09 g = 449.4 g
O: 18 × 16.00 g = 288.0 g
Total mass = 818.4 g
The mass percentage of silicon is:
(449.4 g / 818.4 g) × 100% = 54.91%
Explanation:
An ionic solution is when a compound's ions in an aqueous solution have dissociated. As you combine two aqueous solutions, a reaction occurs. This is when you find out whether or not a precipitate is going to form. A precipitate occurs when the ion reaction component in water is insoluble.The formation of a precipitate is an indication that a chemical change has occurred. for example if we mix clear solutions of silver nitrate and sodium chloride, sodium nitrate is formed which is a precipitate.
Answer:
Before we get into the first law of thermodynamics we need to understand the relation between heat and work and the concept of internal energy. Just like mass, energy is always conserved i.e. it can neither be created nor destroyed but it can be transformed from one form to another. Internal energy is a thermodynamic property of the system that refers to the energy associated with the molecules of the system which includes kinetic energy and potential energy.
Whenever a system goes through any change due to interaction of heat, work and internal energy, it is followed by numerous energy transfer and conversions. However, during these transfers, there is no net change in the total energy.
Similarly, if we look at the first law of thermodynamics it affirms that heat is a form of energy. What it means is that the thermodynamic processes are governed by the principle of conservation of energy. The first law of thermodynamics is also sometimes referred to as the Law of Conservation of Energy
Explanation: