Answer: 19.4 g/cm3
Explanation: density is the relationship between mass over volume.
So density of gold is 15.7g/0.81cm3 = 19.4 g/cm3
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 : The disadvantage of using hydropower is Land can be flooded, displacing people and wildlife
Explanation :
Hydropower is a renewable source of energy. In hydropower, electricity is generated using the mechanical energy of moving water.
Since the kinetic energy is necessary to move the turbines, it is essential that the hydropower plant is present near a water source which has moving water.
It is the most efficient way of harnessing the energy from naturally available energy sources. It does not produce any waste. It does not pollute water or air.
Since hydropower needs kinetic energy of moving water, there is always a possibility of nearby land getting flooded. This would affect the people and wildlife of nearby areas.
Therefore the disadvantage of using hydropower is that land can be flooded, displacing people and wildlife
Answer:
Order zero
Explanation:
Let's consider the decomposition of ammonia to nitrogen and hydrogen on a tungsten filament at 800°C.
2 NH₃(g) → N₂(g) + 3 H₂(g)
The generic rate law is:
rate = k × [NH₃]ⁿ
where,
rate: reaction rate
k: rate constant
n: reaction order
When n = 0, we get:
rate = k × [NH₃]⁰ = k
As we can see, when the reaction order with respect to ammonia is zero, the reaction rate is independent of the concentration of ammonia.
