im not understanding the question, but if its a solid then the reactants are precipitate
To answer this expression we should follow the mathematical rule. The mathematical rule that we will follow is called BODMAS short for brackets, powers, divide, multiply, add, subtract. So, we will first solve the one in the brackets which is <span>(72.61 - 68.59) is equal to 4.02 then we will multiply this to 18.76 and the answer is 75.4152.</span>
Burning a magnesium ribbon in the air is an addition reaction while heating potassium manganate 7 is a decomposition reaction.
<h3>Addition and decomposition reactions</h3>
Magnesium burns in air to produce magnesium oxide as follows:

Potassium manganate 7 burns to produce multiple products as follows:

Thus, the MgO will be heavier than Mg. On the other hand,
will be less heavy than
.
More on reactions can be found here: brainly.com/question/17434463
#SPJ1
Answer:
Mass = 29.23 g
Explanation:
Given data:
Volume of solution = 814.2 mL 814.2/1000 = 0.8142 L)
Molarity of solution = 0.227 M
Mass of solute in gram = ?
Solution:
Molarity = number of moles / volume in L
By putting values,
0.227 M = number of moles / 0.8142 L
Number of moles = 0.227 M × 0.8142 L
Number of moles = 0.184 mol
Mass in gram:
Mass = number of moles × molar mass
Molar mass of calcium acetate = 158.17 g/mol
Mass = 0.184 mol × 158.17 g/mol
Mass = 29.23 g
The electron is travelling with a velocity of 1.123 × 10⁷m/s if it has a wavelength of 8.20 km.
<h3>How to calculate velocity of an electron?</h3>
The velocity at which an electron travels can be calculated using the following formula:
λ = h/mv
Where;
- H = Planck's constant
- m = mass of electron
- v = velocity of electron
- λ = wavelength
- Planck's constant (h) = 6.626 × 10−³⁴ J⋅s.
- mass of electron (m) = 9.109 × 10−³¹ kg
- wavelength = 8200m
8200 = 6.626×10−³⁴ / 9.109 × 10−³¹V
8200 = 7.3 × 10-⁴V
V = 8200 ÷ 7.3 × 10-⁴
V = 1.123 × 10⁷m/s
Therefore, the electron is travelling with a velocity of 1.123 × 10⁷m/s if it has a wavelength of 8.20 km.
Learn more about velocity at: brainly.com/question/13171879
#SPJ1