Answer:
Potassium is an element, with the symbol K
Explanation:
An element is something that cannot be broken down any further, for example, calcium, its Ca.
A compound is when you bond two or more elements. Compounds can be broken down into its original elements, for example, H₂O, it contains two atoms of hydrogen and one atom of oxygen (both hydrogen and oxygen are elements).
Answer:
Speed is measured over time.
Explanation:
Answer: Yes we agree with the student's claim.
Explanation:
When the molecules are present in smaller size, more reactants can react as decreasing the size increases the surface area of the reactants which will enhance the contact of molecules.Hence, more products will form leading to increased rate of reaction.
On increasing the temperature will make more reactant molecules will have sufficient energies to cross the energy barrier and thus the number of effective collisions increases, thus leading to more products and increased rate of reaction.
When the solution is stirred , the molecule's kinetic energy and thus the rate of reaction increases.
Thus smaller size, stirring and increase of temperature will make the solution quickly.
Molarity is defined as the ratio of number of moles to the volume of solution in litres.
The mathematical expression is given as:
Here, molarity is equal to 1.43 M and volume is equal to 785 mL.
Convert mL into L
As, 1 mL = 0.001 L
Thus, volume = 
= 0.785 L
Rearrange the formula of molarity in terms of number of moles:
n = 
= 1.12255 mole
Now, Number of moles = 
Molar mass of potassium hydroxide = 56.10 g/mol
1.12255 mole = 
mass in g = 
= 62.97 g
Hence, mass of 
= 62.97 g
