There are two hydrogen atoms in one molecule of water.
The answer is B) 2
Answer: Options (a) and (d) are the correct answer.
Explanation:
A catalyst is the substance which helps in increasing the rate of reaction.
Activation energy is the minimum amount of energy required by reactants to start the reaction. On addition of catalyst, the path of reaction changes because the energy barrier gap reduces and hence, the activation energy also decreases.
In the absence of catalyst, we need to increase the temperature so that reaction can occur quickly.
Whereas on addition of catalyst, there is no need to increase the temperature as the catalyst itself is sufficient to increase the rate of reaction. As a result, temperature should be lowered when there is addition of catalyst in the reaction.
Thus, we can conclude that catalysts can save money by essentially lowering the activation energy and temperature required.
Answer:
Heat transfer = Q = 62341.6 J
Explanation:
Given data:
Heat transfer = ?
Mass of water = 50.0 g
Initial temperature = 30.0°C
Final temperature = 55.0°C
Specific heat capacity of water = 4.184 J/g.K
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 55.0°C - 30.0°C
ΔT = 25°C (25+273= 298 K)
Q = 50.0 g × 4.184 J/g.K ×298 K
Q = 62341.6 J
Answer:
The number of atoms in the gemstones of that tiara is 
.
Explanation:
Number of diamonds ion tiara = 888
Mass of each diamond = 1.0 carat = 0.200 g (given)
Mass of 888 diamonds in tiara:
Given that diamond is a form of carbon.
Atomic mass of carbon atom = 12 g/mol
Moles of 77.600 g of carbon =
Number of atoms of carbon 14.800 moles:
The number of atoms in the gemstones of that tiara is .
The atomic radius increases down a column (group) and decreases along a row
