Answer:62.66°C or 235.66K
Explanation:Q=McpT, the energy was given in calories so you first convert to Joules by multiplying the value in calories by 4.184J.
17*4.184=71.128kJ.
71.128kJ=mcpT
71.128kJ=245*4.187*(T-Tm)
Tm is the final temperature of the mixture. The T is the temperature given which should be converted to Kelvin by adding 273...T=32+273=305K.
71128J=245*4.187*(305-Tm)
71128=312873.575-1025.815Tm
1025.815Tm=312873.575-71128
1025.815Tm=241745.58
Tm=241745.58/1025.815
Tm=235.66K
Answer:
5.8μg
Explanation:
According to the rate or decay law:
N/N₀ = exp(-λt)------------------------------- (1)
Where N = Current quantity, μg
N₀ = Original quantity, μg
λ= Decay constant day⁻¹
t = time in days
Since the half life is 4.5 days, we can calculate the λ from (1) by substituting N/N₀ = 0.5
0.5 = exp (-4.5λ)
ln 0.5 = -4.5λ
-0.6931 = -4.5λ
λ = -0.6931 /-4.5
=0.1540 day⁻¹
Substituting into (1) we have :
N/N₀ = exp(-0.154t)----------------------------- (2)
To receive 5.0 μg of the nuclide with a delivery time of 24 hours or 1 day:
N = 5.0 μg
N₀ = Unknown
t = 1 day
Substituting into (2) we have
[5/N₀] = exp (-0.154 x 1)
5/N₀ = 0.8572
N₀ = 5/0.8572
= 5.8329μg
≈ 5.8μg
The Chemist must order 5.8μg of 47-CaCO3
STP is abbreviation for Standard Temperature and Pressure at which the temperature is 273 K and pressure is 1 atm
- At these conditions the molar volume is equal to 22.4 L
so 1 mole of SO₂ volume = 22.4 L
? mole of SO₂ volume = 2.5 L
number of moles = 2.5 / 22.4 = 0.1116 mol
mass of SO₂ = 0.1116 * 64.063 = 7.15 g
In every reaction, mass cannot be destroyed nor created as defined by the law of conservation of mass. Energy also cannot be destroyed when a chemical reaction takes place
Answer: 1.46moles
Explanation:
Applying PV= nRT
P= 1atm, V= 32.6L, R= 0.082, T = 273K
Substitute and simplify
1×32.6/(0.082×273)=n
n= 1.46moles
