Answer : The correct options are,
and 
Explanation :
Single displacement reaction : It is a type of chemical reaction in which the more reactive element displaces the less reactive element.
Option A reaction : 
It is an example of double displacement reaction because in this reaction a positive cation and a negative anion of the two reactants exchange their places to form two new products.
Option B reaction : 
It is an example of single displacement reaction.
Option C reaction : 
It is an example of combination reaction because in this reaction two reactants react to give a single product.
Option D reaction : 
It is an example of decomposition reaction because in this reaction a single reactant decomposes into two or more products.
Option E reaction : 
It is an example of single displacement reaction because in this reaction the most react element, aluminium displaces the less reactive element, hydrogen.
Hence, the options B and E are single displacement reactions.
<span>Helium is the noble gas with only 2 valence electrons
I Hope This helps
</span>
When we wish to convert a gas to liquid we have to either
a) decrease temperature
b) increase pressure
In case of fire extinguisher the CO2 is found to be in liquid state, this is as the CO2 is pressurized at high pressure which keeps CO2 in liquid state
the ideal pressure and temperature conditions when CO2 gas can be converted to CO2 gas
Pressure = 5 - 73 atm
Temperature = -57 to 31 degree Celsius
Answer:
Compared to early humans our brains seemed to have increased in size, and part of the cause may be because of things like Climage change, ecology and social competition
Explanation: