D. A ll of the above. catalyst reduces the activation energy thereby making the reaction faster. an increase in temperature increases the kinetic energy and no of collisions making reaction faster for an endothermic reaction while decrease in temperature favors an exothermic reaction.
increase in concentration increases the molecules reacting so the reaction is faster and vice versa.
Answer:
The energy difference between these 2p and 2s orbitals is 
Explanation:
Wavelength of the photon emitted = 
Energy of the photon will corresponds to the energy difference between 2p and 2s orbital = E
Energy of the photon is given by Planck's equation:

h = Planck's constant = 
c = Speed of the light = 


The energy difference between these 2p and 2s orbitals is 
Answer:
M=Molarity
V=volume
change millilitre to litre
so:15ml=0.015 L
:38.5ml=0.0385 L
M1V1=M1V1
M1* 0.015 L= 0.15M*0.0385 L
M1=0.00385
To measure length scientists may use rulers, meter sticks, etc. and to measure mass they may use a balance.