Hey there!
A half-life means after a certain amount of time, half of that substance will have decayed after that time.
An equation for exponential decay is the following:
y = a(1 - b)ⁿ
Where a is the original amount, b is the rate of decay, and n is time.
1000 is about 0.3 of a half life, 1000 divided by 138 days (3312 hours) is approximately 0.3.
Let's plug in values to that equation:
y = 321(1 - 0.5)^(0.3)
Simplify.
y = 260.73
There will be 260.73mg of polonium-210 remaining after 1000 hours.
Hope this helps!
Answer:
A. 0 N
Explanation:
One force is subtracted from the other to calculate the net force. If the opposing forces are equal, or balanced, the net force is zero.
Hope this helps!
kg and all the given units are units used to measure mass.
kg is the standard unit to measure mass
lets find the value of 0.00684 kg in all the given units
a. dkg
1 kg is equivalent to 100 decagram (dkg)
therefore 0.00684 kg is = 100 dkg/kg x 0.00684 kg = 0.684 dkg
this is not the given value therefore this choice is incorrect
b. 1 kg is equivalent to 1000 g
therefore 0.00684 kg = 1000 g/kg x 0.00684 kg = 6.84 g
this is the given value so this is correct
c. 1 kg is equivalent to 100 000 centigrams (cg)
therefore 0.00684 kg = 100 000 cg/kg x 0.00684 kg = 684 cg
this is the given value so this is also correct
d) 1 kg is equivalent to 1 000 000 mg
therefore 0.00684 kg = 1 000 000 mg/kg x 0.00684 kg = 6 840 mg
this too is correct
the incorrect answer is A. 0.0684 dkg
Answer:
2,3 -Dimethyl pentane
Explanation:
The given molecule is 2,3-Dimethyl pentane.
First of all select the longest chain of C-C atom. This will be the parent name.
In given structure the longest chain is straight chain that contain five carbon. Thus the parent name will pentane and there is no double or triple bond the given structure is of alkane.
Than locate the positions of functional groups attached.
In given structure there are two methyl groups are present. Give the name in such a way that functional groups will have lowest number. In given case we will start from the left.
The first methyl group will have number 2 and second will have number 3.
The name will be,
2,3-Dimethyl pentane
Answer:
8.82 kg es la masa total de leche
Explanation:
Consideraremos que el volumen de cada bolsa de leche es de 900 mL.
Sabiendo que tenemos en total 7 bolsas, el volumen final en litros que tenemos disponible es de:
900 mL . 7 = 6300 mL
Utilizando la densidad podemos calcular la masa de leche que tenemos en el total de las 7 bolsas
Densidad = masa / volumen
Densidad . volumen = masa → 1.4 g/mL . 6300 mL = 8820 g
Convertimos la masa de gramos a kg
8820 g . 1 kg /1000g = 8.82 kg
