Answer:
See explanation
Explanation:
a) u= 60 m/s, v= 45 m/s, t = 7 secs
From;
v = u + at
a = v - u/t
a= 45 - 60/7
a = -2.14 m/s^2
b)
u = 200 m/s
v= 235 m/s
t = 30 secs
v = u + at
a = v-u/t
a = 235 - 200/30
a= 1.17 m/s^2
c)
i) Acceleration = 3 - 1/2-0 = 2/2 = 1 m/s^2
ii) The slope between 2 and 5 is zero because velocity was not changing with time.
iii) Within the time between 2 and 5 the speed remained at 3 m/s
iv) the slope between 5 and 8 is 2 - 3/8 - 5 = -1/3 = -0.33m/s^2
v) The negative slope means that velocity is decreasing with time(deceleration).
In titration, the moles of acid equal moles of base. You were given that 22.75ml of 0.215M NaOH is used, so calculate the number of moles of that base the experiment used in total. After that because you know mol base = mol acid, whatever amount of base you use must be the total amount of acid present in the solution. You were given the volume of the acid, and you have just found the total mols of acid. Using these two information, solve for the concentration. And one more thing, even though I'm pretty sure it won't affect your answer, you should always convert things to the proper units. Since the concentration we're talking about in this problem is molarity, which has the unit mol/L, you should always have all of your numbers in these units. It just make it simpler and will not confuse you
The amount of energy released when 0.06 kg of mercury condenses at the same temperature can be calculated using its latent heat of fusion which is the opposite of melting. Latent heat of fusion and melting can be used because they have the same magnitude, but opposite signs. Latent heat is the amount of energy required to change the state or phase of a substance. For latent heat, there is no temperature change. The equation is:
E = m(ΔH)
where:
m = mass of substance
ΔH = latent heat of fusion or melting
According to data, the ΔH of mercury is approximately 11.6 kJ/kg.
E = 0.06kg (11.6 kJ/kg) = 0.696 kJ or 696 J
The answer is D. 697.08 J. Note that small differences could be due to rounding off or different data sources.
Answer:
it is a physical change because when you heat up again a solution of sugar and tea you gonna obtain again sugar
