(4) 220Fr, known as Francium-220, undergoes alpha decay, which emits an alpha particle, also known as a helium nucleus, which has a charge of +2.
Answer:
The mass of a solute divided by the mass of a solution times 100
Explanation:
The concentration of a solution refers to how much of a solute is dissolved in an amount of solvent. To express this concentration exist different methods, the mass percent concentration is one of them and is <em>defined as the mass of a solute divided by the mass of a solution times 100:</em>
<em>%m/m= (mass of a solute/mass of solution)x100</em>
<em>Where the mass of the solution is the sum of the mass of solute and mass of solvent.</em>
%m/m is commonly used when you can measure the masses of both solute and solution.
I hope you find this information useful and interesting! Good luck!
Answer:
λ = 5.56 × 10⁻³ m
Explanation:
You have to use the formula c = λv to solve the problem. Review what you are given. You are given v and c, where v = 5.40 × 10¹⁰ Hz and c = 3.00 × 10⁸ m/s. The value c is for the speed of light and is something you need to memorize. You will use it often in physics and sometimes in chemistry.
Now that you figured out what you know, you can see that there is only one unknown, allowing you to solve.
c = λv
λ = c/v
λ = (3.00 × 10⁸ m/s)/(5.40 × 10¹⁰ Hz)
λ = 5.56 × 10⁻³ m
Hello!
<span>A chemical that will ignite spontaneously in air at a temperature of 130 degree fahrenheit (54.4 degree celsius) or below is identified by the term pyrophoric.
Pyrophoric substances are those that ignite spontaneously when in contact with air at 130 °F or below. Some substances that are pyrophoric include Iron Sulfur (FeS) or some metals like finely powdered Uranium. To handle pyrophoric substances, it is required to work in an inert atmosphere (i.e. an atmosphere without oxygen).
Have a nice day!</span>
Answer:
pH = 4.26
Explanation:
Bromocresol green is a commonly used pH indicator. The concentration ratio of the acid form to base form explains its color, which reflects the pH of the medium.
C₂₁H₁₄Br₄O₅S + H₂O ⇄ C₂₁H₁₃Br₄O₅S⁻ + H₃O⁺
acid conjugate base
We can calculate the pH through Henderson-Hasselbalch's equation:
![pH=pKa+log(\frac{[base]}{[acid]} )=4.66+log(\frac{1}{2.49} )=4.26](https://tex.z-dn.net/?f=pH%3DpKa%2Blog%28%5Cfrac%7B%5Bbase%5D%7D%7B%5Bacid%5D%7D%20%29%3D4.66%2Blog%28%5Cfrac%7B1%7D%7B2.49%7D%20%29%3D4.26)
