Answer:
Here's it.
Explanation:
Concentrated acids are very corrosive and dangerous chemicals that are commonly encountered in the laboratory. ... Concentrated acids may be fatal if inhaled; and can cause severe eye and skin burns, severe respiratory and digestive tract burns. Contact with other materials may cause a fire.
A beaker of black powder can be a mixture with different substances (i.e gunpowder: a mixture of sulfur, charcoal, etc.), an element which can probably be carbon (known as black), and a compound as well which can be potassium nitrate. Hence, the answer is D.
B. Magnesium + Hydrogen Sulfide (Reactors) ----> Magnesium Sulfide + Hydrogen (Products)
Answer:
0.0905 M
Explanation:
Let's consider the neutralization reaction between H2SO4 and KOH.
H₂SO₄ + 2 KOH → K₂SO₄ + 2 H₂O
22.87 mL of 0.158 M KOH react. The reacting moles of KOH are:
0.02287 L × 0.158 mol/L = 3.61 × 10⁻³ mol
The molar ratio of H₂SO₄ to KOH is 1:2. The reacting moles of H₂SO₄ are 1/2 × 3.61 × 10⁻³ mol = 1.81 × 10⁻³ mol
1.81 × 10⁻³ moles of H₂SO₄ are in 20.0 mL. The molarity of H₂SO₄ is:
M = 1.81 × 10⁻³ mol / 0.0200 L = 0.0905 M
- The change in color from blue to pink of the cobalt complexes here has been the basis of cobalt chloride indicator papers for the detection of the presence of water. It is also used in self-indicating silica gel desiccant granules.
- Pink cobalt species + chloride ions ⇌ Blue cobalt species + water molecules
<u>Explanation</u>:
- The adjustment in color from blue to the pink of the cobalt complexes here has been the premise of cobalt chloride indicator papers for the detection of the presence of water. It is likewise utilized in self-demonstrating silica gel desiccant granules.
Pink cobalt species + chloride particles ⇌ Blue cobalt species + water molecules
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The response of [Co(H2O)6]2+(aq) + 4Cl–(aq) → [CoCl4]2–(aq) + 6H2O(l) is endothermic. In this manner, as per Le Chatelier's rule, when the temperature is raised, the situation of the balance will move to one side, shaping a greater amount of the blue complex particle at the expense of the pink species.
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Including concentrated hydrochloric raises the chloride particle fixation, making the equilibrium move to one side, as per Le Chatelier. Including water brings down the chloride particle fixation, moving the equilibrium the other way.
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As an extension, it is conceivable to show that it is the Cl–particles in the hydrochloric acid that move the balance by including a spatula of sodium chloride rather than the pink arrangement. This delivers a bluer color, however, this may take some time because the salt is delayed to dissolve.
