Answer:
A) 54.04%
B) 13-karat
Explanation:
A) From the problem we have
<em>1)</em> Mg + Ms = 9.40 g
<em>2)</em> Vg + Vs = 0.675 cm³
Where M stands for mass, V stands for volume, and g and s stand for gold and silver respectively.
We can rewrite the first equation using the density values:
<em>3)</em> Vg * 19.3 g/cm³ + Vs * 10.5 g/cm³ = 9.40
So now we have<em> a system of two equations</em> (2 and 3) <em>with two unknowns</em>:
We <u>express Vg in terms of Vs</u>:
We <u>replace the value of Vg in equation 3</u>:
- Vg * 19.3 + Vs * 10.5 = 9.40
- (0.675-Vs) * 19.3 + Vs * 10.5 = 9.40
- 13.0275 - 19.3Vs + 10.5Vs = 9.40
Now we <u>calculate Vg</u>:
- Vg + 0.412 cm³ = 0.675 cm³
We <u>calculate Mg from Vg</u>:
- 0.263 cm³ * 19.3 g/cm³ = 5.08 g
We calculate the mass percentage of gold:
- 5.08 / 9.40 * 100% = 54.04%
B)
We multiply 24 by the percentage fraction:
- 24 * 54.04/100 = 12.97-karat ≅ 13-karat
Answer:
0.92^n
Explanation:
Given that :
Initial amount of vinegar = 1 Litre
Number of litres removed repeatedly = 0.08 Litre
Since the amount removed each time is constant, then ;
Initial % = 100% = 100/100 = 1
. Using the relation :
Amount of vinegar in mixture :
Initial * (1 - amount removed / initial amount)^n
n = number of times repeated
1 * (1 - 0.08/1)^n
1 * (1 - 0.08)^n
1 * 0.92^n
Hence,
For nth removal,
Concentration will be :
0.92^n ; for n ≥ 1
3! You have to ensure balance of all the different elements.
The answer is C. The answer is C because if u increase the surface area, the more reactants u will get. and if u get more The reactants will move faster. Hoped that Helped!:-)
Hey there!
Cu(CN)₂
Find the molar mass.
Cu: 1 x 63.546 = 63.546
C: 2 x 12.01 = 24.02
N: 2 x 14.07 = 28.14
-----------------------------------
115.706 grams
The mass of one mole of Cu(CN)₂ is 115.706 grams.
We have 4 moles.
115.706 x 4 = 463
4.00 moles of Cu(CN)₂ has a mass of 463 grams.
Hope this helps!