Answer:
The answer to your question is Mercury
Explanation:
The flame test essay is used to identify the identity of a substance because most elements show different colors when in flame.
There are many elements that burn violet when in flame especially elements of the group IA like Potassium, Rubidium, Cesium and also Cyanide and Mercury located in different groups.
But the bibliography tells us that Mercury chloride burns violet so this element is the correct answer because there is chloride in the sample of this question.
In 1871, a Russian Chemist, Dimitri Mendeleev, gave a useful scheme for classification of elements. He presented the first regular periodic table in which elements of similar chemical properties were arranged in eight vertical columns called groups. The horizontal rows of table were called periods. He arranged elements in ascending order of their atomic masses and found that elements having similar chemical properties appeared at regular intervals. This observation was called Periodic Law.
<h2>Answer : By weighing the costs and benefits of an environmental issue
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Explanation :</h3>
The law makers usually conduct many studies before a law is imposed. They try to explore many other options available to the current environmental issue and then come to a conclusion to make a law.
They also weigh the cost aspect along with the benefit of the ongoing environmental issue. They try to come up with something which appears to be cost effective and result bearing.
A gaseous product is formed
Urea is highly soluble in water. When it is allowed to dissolve in water in the presence of heat, it will yield ammonia and carbon dioxide. The reaction is shown below:
<span>NH2-CO-NH2 + H2O </span>⇒ 2 NH3 + CO2
As you can observe in the stoichiometric equations, 1 molecule of water can dissolve with 1 mole of urea.