Answer: The forensic examination of substances involve a preliminary flame test.
Explanation:
The forensic chemical analysis of samples involves the flame testing which is one of the preliminary test. The materials are burned on a flame and the color of the flame is considered indicative of the elements present in the material.
The substances like Borax (sodium borate), Copper(II) sulfate, and boric acid burn with a characteristic green flame.
Answer:
D.) store water, waste, and nutrients for the cell.
Explanation:
D is your answer because the vacuole is like a closet for the cell. It can store anything the cell may use later or it can store waste that is to be taken out of the cell at a later time as to not contaminate the rest of the organelles. In plant cells, it can also help with support since it is so big.
Answer: The correct answers are A and B.
Explanation:
Conduction: In the conduction, the heat is
transferred from the hotter body to the colder
body until the temperature on both bodies are
equal.
In thermal equilibrium, there is no heat
transfer as the heat is transferred till the
temperature on the bodies are not same.
In the given problem, an iron bar at 200°C is
placed in thermal contact with an identical iron
bar at 120°C in an isolated system. After 30
minutes, the thermal equilibrium is attained.
Then, the temperature on both iron bars are
equal.Both iron bars are at 160°C in an isolated
system.
But in an open system, the temperatures of the
iron bars after 30 minutes would be less than
160°C. There will be heat lost to the
surrounding. The room temperature is 25°C.
There will be exchange of the heat occur
between the iron bars and the surrounding. But
It would take more than 30 minutes for both iron
bars to reach 160°C because heat would be
transferred less efficiently.
Therefore, the correct options are (A) and (B).
Answer:
Final T = 298.7K
Explanation:
In this problem, the heat given for the iron is equal to the heat that water absorbs. Using the equation:
Q = C*m*ΔT
<em>Where Q is heat given = 270000J</em>
<em>C is specific heat of substance = 0.385J/gK</em>
<em>m is mass of iron = 1000g</em>
<em>ΔT is change in temperature = Initial temperature - Final temperature.</em>
<em />
270000J = 0.385J/gK*1000g*(1000K-Final temperature)
701.3J/K = 1000K - Final T
<h3>Final T = 298.7K</h3>
Reaction is producing more reactants than products