(a) 43.6 mg; (b) 520 mg
(a) <em>Mass of phosphoric acid (PA) in a dose
</em>
Mass of PA = 2 tsp × (21.8 mg PA/1 tsp) = 43.6 mg PA
(b) <em>Mass of PA in the bottle
</em>
<em>Step 1</em>. Convert <em>ounces to millilitres
</em>
Volume = 4 oz × (30 mL/1 oz) = 120 mL
<em>Step 2.</em> Calculate the mass of PA
Mass of PA = 120 mL × (21.8 mg PA/5 mL) ≈ 520 mg PA
Answer:
(1) order = 2
(2) R = K [A]²
Explanation:
Given the reaction:
A--------->Product
The rate constant relation for the reaction is given as:
R(i) = K [A]............(*)
Where R(I) is rate constant at different concentration of A.
Taking the rate constant as R1, R2 and R3 for the different concentrations respectively. Then the following equations results
0.011 = K [0.15] ⁿ.........(1)
0.044 = K [0.30]ⁿ .......(2)
0.177 = K [0.60]ⁿ .........(3)
Dividing (2) by (1) and (3) by (1)
Gives:
0.044/0.011 = [0.3/0.15]ⁿ
4 = 2ⁿ; 2² = 2ⁿ; n = 2
Similarly
0.177/0.011 = [0.60/0.15]ⁿ
16.09 = 4ⁿ
16.09 = 16 (approximately)
4² = 4ⁿ ; n = 2
Hence the order of the reaction is 2.
The rate law is R = K [A]²
Density = mass / volume so mass = density x volume. Therefore mass = 2.70 x 348 = 939.6g
<span>carbon + oxygen → carbon dioxide</span>
Answer:
Some indicators of rusting include:
a. color change
b. formation of as solid
Explanation:
Rusting is a redox ( a reaction in which reduction and oxidation occur concurrently) reaction which occcur when metallic iron is exposed to air and water or water vapor reacts with the oxygen and water to form a hydrated mixture of oxides of the metal.
The shiny metallic iron becomes oxidized to Fe²⁺ and Fe³⁺ ions while neutral oxygen gas molecules are reduced to O²⁻ ions. The shiny metallic iron also loses its lustrous appearance as the process proceeds and is covered by a layer of rust.
The equation for reaction is given below:
4Fe(s) + 30₂(g) + xH₂O(l) -----> 2Fe₂O₃. xH₂O(s)
The product of the reaction above is known as rust and is reddish-brown solid.
Rusting causes iron to become flaky and weak as rust is very light and porous, reducing the strength and appearance of iron which are desirable properties of iron when used in construction. The rusting of iron can lead to damage to automobiles, railings, bridges, and several other iron structures.
