Answer:
Y = 92.5 %
Explanation:
Hello there!
In this case, since the reaction between lead (II) nitrate and potassium bromide is:
Exhibits a 1:2 mole ratio of the former to the later, we can calculate the moles of lead (II) bromide product to figure out the limiting reactant:
Thus, the limiting reactant is the KBr as it yields the fewest moles of PbBr2 product. Afterwards, we calculate the mass of product by using its molar mass:
And the resulting percent yield:
Regards!
Answer:
see explanation
Explanation:
Ice usually has tightly packed molecules at a low temperature. When it comes in contact with a higher temperature or room temperature, the ice molecules gain energy and the molecular tension increases which causes the state to change to liquid. Therefore, a <u>high temperature</u> causes an ice block to melt.
Answer:
k = -0.09165 years^(-1)
Explanation:
The exponential decay model of a radioactive isotope is generally given as;
A(t) = A_o(e^(kt))
Where;
A_o is quantity of isotope before decay, k is decay constant and A(t) is quantity after t years
We are given;
A_o = 5 kg
A(10) = 2kg
t = 10 years
Thus;
A(10) = 2 = 5(e^(10k))
Thus;
2 = 5(e^(10k))
2/5 = (e^(10k))
0.4 = (e^(10k))
In 0.4 = 10k
-0.9164 = 10k
k = -0.9164/10
k = -0.09165 years^(-1)
Answer:
moles Na = 0.1114 g / 22.9898 g/mol=0.004846
moles Tc = 0.4562g /98.9063 g/mol=0.004612
mass O = 0.8961 - ( 0.1114 + 0.4562)=03285 g
moles O = 0.3285 g/ 15.999 g/mol=0.02053
divide by the smallest
0.02053/ 0.004612 =4.45 => O
0.004846/ 0.004612 = 1.0 => Tc
to get whole numbers multiply by 2
Na2Tc2O 9
Explanation:
Hope it right hope it helps
Answer:
Final T° is 45.5°C
Explanation:
Formula for calorimetry is:
Q = m . C . ΔT , where
ΔT = Final T° - Initial T°
C = Specific heat
m = mass
Let's replace with the data given
305 J = 93.4 g . 0.128 J/g°C . (Final T° - 20°C)
305 J / 93.4 g . 0.128 J/g°C = Final T° - 20°C
25.5°C = Final T° - 20°C → Final T° = 25.5°C + 20°C = 45.5°C
