A nucleus of mass number 81 contains 46 neutrons
Mass number=number of protons+number of neutrons
81=number of protons+ 46
number of protons=81-46
number of protons=35
In an atom, number of electrons=number of protons=35
So, the element is ⁸¹Br₃₅ .
Atomic ion of Br, having 36 electrons in it will be:
⁸¹Br⁻₃₆
The symbol for this atomic ion will be Br and charge on the ion will be -ve.
Answer:
391.46 L
Explanation:
Given:
Initial temperature of the water = 23.4°C
Final temperature of the water = 39°C
Temperature change for the water, ΔT = (39 - 23.4) = 15.6°C
Heat absorbed by the water = 2.55 × 10⁴ kJ = 2.55 × 10⁷ J
Density of the water = 0.998 g/mL
Specific heat of the water, C = 4.184 J/g°C
Now,
The heat absorbed by the water, q = mCΔT
where, m is the mass of the water
Thus,
we have
2.55 × 10⁷ J = m × 4.184 × 15.6
or
m = 390682.45 grams
also,
Density = mass / volume
thus,
0.998 = 390682.45 / volume
or
Volume = 391465.38 mL
or
Volume = 391.46 L
Answer:
18
Explanation:
6 (weights) x 3 (distance) = moment
At STP, 1 mol = 22.4
1 mol = 6.022 X 10^ 23
so your answer is right it is B 6.022 X 10^ 23
Answer:
Explanation:
Hello!
In this case, since the combustion of the hamburger released 335.4 kcal of energy and that energy is received by the calorimeter, we can write:
And the heat of the calorimeter is written in terms of the temperature change and the calorimeter constant:
Thus, given the released heat by the hamburger due to its combustion and the temperature change, Cv for the calorimeter turns out:
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