Moles are used conveniently in chemistry especially in stoichiometric calculations involving reactions. The unit of mole is a collective term that holds 6.022×10^23 particles. These particles is a general term for any small units of matter including molecules, atoms and sub-particles. This ratio of 6.022×10^23 particles to 1 mole is known to be the Avogadro's number. Its exact number is actually <span>6.0221409</span>×10^23. We use this constant in our stoichiometric calculation as follows:
15 moles oxygen * (6.022×10^23 molecules/ 1 mole oxygen) = 9.033×10^24 molecules of oxygen
The best statement
which describes a reaction in a state of equilibrium is letter D. <span>The rate of the forward
reaction equals the rate of the reverse reaction and the </span>concentrations of products and
reactants are constant.
>Chemical equilibrium<span> is defined as<span> the state in which both reactants and products are present
in </span></span>concentrations<span> which have no further tendency to change with time. This state results when the forward
reaction proceeds at the same rate as the </span>reverse
reaction<span>. The </span>reaction rates<span> of the forward and backward reactions are generally not zero,
but equal. Thus, there are no net changes in the concentrations of the reactant(s)
and product(s).</span>
<span> </span>
Answer:
Mass of water = 41.8 g
Explanation:
Given data:
Mass of water = ?
Change in temperature = 3.0 °C
Specific heat capacity = 4.184 j/g.°C
Heat absorbed = 525 j
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 = 3.0°C
Now we will put the values in formula.
525 J = m × 4.184 j/g.°C × 3.0°C
525 J = m × 12.552 j/g
m = 525 J/ 12.552 j/g
m = 41.8 g
The crest is cover distance. <span>The </span>speed<span> of a wave indicate how fast wave is moving. </span>T<span>he speed is the distance traveled by a crest in a given interval of time. Greater distance in same amount of time means wave travel faster.
speed of wave = distance/time.
speed of wave = 0,2 m </span>÷ 0,2 s = 1 m/s.