Answer:
0,3457 grams equal to 345.7mg
Explanation:
1000 mg-------1 g
345.7mg------x= (345.7mgx 1 g)/1000mg= <em>0,3457 g</em>
Answer:
Synthesis reaction:
Explanation:
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
A + B → AB
All other options are incorrect because,
Single replacement:
It is the reaction in which one elements replace the other element in compound.
AB + C → AC + B
Decomposition reaction:
It is the reaction in which one reactant is break down into two or more product.
AB → A + B
Combustion reaction:
In combustion reaction substances are react with oxygen and produces carbon dioxide and water.
With that informatio you can:
1) Write the chemical equation
2) Balance the chemical equation
3) State the molar ratios
4) Predict if precipitation occurs.
I will do all four, for you:
1) Chemical equation:
mercury(I) nitrate potassium bromide mercury(I) bromide potassium nitrate
<span>Hg2(NO3)2 + KBr → Hg2Br2 + KNO<span>3
2) Balanced chemical equation
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<span>Hg2(NO3)2 + 2KBr → Hg2Br2 + 2KNO<span>3
3) Molar ratios or proportions:
1 mol </span></span><span>Hg2(NO3)2 : 2 mol KBr : 1 mol Hg2Br2 : 2 mol KNO<span>3
4) Prediction of precipitation.
You can use the solubility rules or a table of solubilities. I found in a table of solutiblities that mercury(I) bromide is insoluble and potassium bromide is soluble, Then you can predict that the precipitation of mercury(I) bromide will occur.
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Answer:
- The option <u><em>B) Fe₂O₃ (s) + 3C(s) → 2Fe(s) + 3CO₂(g),</em></u> because the reactants are only solid units and the products contain gas molecules.
Explanation:
A <em>positive entropy change</em> means that the entropy of the products is greater than the entropy of the reactants.
Entropy in a measure of the radomness or disorder of the system.
Let's see every reaction:
<u />
<u>A) 4NO₂ (g) + 2 H₂O (l) + O₂ (g) → 4 HNO₃ (aq)</u>
Since 5 molecules of a gas (high disorder) combines with 2 molecules of liquid to produce 4 units of aqueous HNO₃ you may expect that the product is more ordered than the reactants, which means that the change in entropy is negative (the entropy decreases).
<u />
<u>B) Fe₂O₃ (s) + 3C(s) → 2Fe(s) + 3CO₂(g)</u>
The left side (reactants) show only solid substances which is a highly ordered arrangement while the right side (products) show the formation a solid (ordered arrangement) and a gas (highly disoredered arrangement), so you can predict the increase of the system entropy, i.e. a positive entropy change.
The <u>equation C)</u> shows the combination of 12 gas molecules to produce 1 solid and 6 gas molecules, so you can expect that the entropy will decrease, i.e. a negative entropy change.
For <u>equation D)</u> the products include solid and gas reactants while the product is just one unit of solid substance, letting you to predict a negative entropy change.
Explanation:
Mike drives his car 60 km in 55minutes. What is its average speed in kilometers per hour ? A train travels 120 km in 2 hours and 30 .
