Given:3.40g sample of the steel used to produce 250.0 mLSolution containing Cr2O72−
Assuming all the Cr is contained in the BaCrO4 at the end.
(0.145 g BaCrO4) / (253.3216 g BaCrO4/mol) x (250.0 mL / 10.0 mL) x (1 mol Cr / 1 mol BaCrO4) x (51.99616 g Cr/mol / (3.40 g) = 0.219 = 21.9% Cr
Answer:
Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay, beta decay, and gamma decay, all of which involve emitting one or more particles or photons.
Explanation:
Answer:
0.5077 moles
Explanation:
Data Given:
Moles = n = <u>???</u>
Temperature = T = 300 K
Pressure = P = 380 mmHg = 0.50 atm
Volume = V = 25 L
Formula Used:
Let's assume that the hydrogen gas in balloon is acting as an Ideal gas, the according to Ideal Gas Equation,
P V = n R T
where; R = Universal Gas Constant = 0.082057 atm.L.mol⁻¹.K⁻¹
Solving Equation for n,
n = P V / RT
Putting Values,
n = (0.50 atm × 25 L) / (0.082057 atm.L.mol⁻¹.K⁻¹ × 300 K)
n = 0.5077 moles
Answer:
1. C = 0.73 M.
2. pH = 0.14
Explanation:
The reaction is the following:
HCl + NH₃ ⇄ NH₄⁺Cl⁻
From the titration, we can find the number of moles of HCl that were neutralized by the ammonia.

Where "a" is for acid and "b" is for base.
The number of moles is:
Where "C" is for concentration and "V" for volume.


Hence the initial concentration of the acid is 0.73 M.
The original pH of the acid is given by:
![pH = -log([H^{+}])](https://tex.z-dn.net/?f=%20pH%20%3D%20-log%28%5BH%5E%7B%2B%7D%5D%29%20)
Therefore, the original pH of the acid is 0.14.
I hope it helps you!