Answer:
because no chemical change is happening
Explanation:
<h3>
Answer:</h3>
20.62 Kilo-joules
<h3>
Explanation:</h3>
- The Enthalpy of combustion of ethyl alcohol is -950 kJ/mol.
- This means that 1 mole of ethyl alcohol evolves a quantity of heat of 950 Joules when burned.
Molar mass of ethyl ethanol = 46.08 g/mol
Therefore;
46.08 g of C₂H₅OH evolves heat equivalent to 950 kilojoules
We can calculate the amount of heat evolved by 1 g of C₂H₅OH
Heat evolved by 1 g of C₂H₅OH = Molar enthalpy of combustion ÷ Molar mass
= 950 kJ/mol ÷ 46.08 g/mol
= 20.62 Kj/g
Therefore, a gram of C₂H₅OH will evolve 20.62 kilo-joules of heat
Explanation:
When the forces acting on an object are balanced , there is no change in the object's motion.
A force acting on a resting object can cause the object to move.
On Earth, gravity pulls all objects toward the ground.
When a force acts in the opposite direction of another force, the forces counteract each other.
More than one force acting on a falling object can reduce its downward acceleration
Air resistance is caused by molecules of air pushing against a moving object
Answer:
Lattice energy is <em>the energy required to convert a mole of ionic solid into its constituent ions in the gas phase</em>
Explanation:
Lattice energy is usually calculated by the Born-Haber cycle, from the affinity energies and sublimation ethalphy values. It is used as an estimation of the ionic energy strength between the ions in an ionic compound.
It is defined as the energy needed to broke 1 mol of a given ionic compound into its ions in the gaseous state. For example, the lattice energy for sodium chloride (NaCl) is the energy required to separate 1 mol of solid ionic compound (NaCl(s)) and produce the sodium and chlorine ions in the gas phase: Na⁺(g) and Cl⁻(g).
Answer:
highest first ionization energy - Br
smallest atomic size - Br
most metallic character - Na
Explanation:
Ionization energy of Br is higher than P because higher zeff value
Sodium is more metallic than calcium because it is able to loose electron more readily as compared to calcium because of higher electro positivity.
Atomic radius of Br is the smallest as its atomic radius is 114, P (115), Ca (197), Na (186)
