<h2>
Answer:</h2>
The magnesium ribbon, <u>D. It forms a material to cast the tool mark</u>.
<h2>
Explanation:</h2>
When a magnesium ribbon is burnt in the presence of oxygen it gives out strong light and heat is produced. Apart from it, it leads to the production of substance called as magnesium oxide which is formed as the product due to the reaction of magnesium with the oxygen present in the air.
Tool marks are the mark which is created by tools while using them. In order to identify or locate them castes made up of magnesium oxide is utilized. When this is pasted on the suspected area, the tool mark of the suspected tool gets pasted on it.
Answer:
1 mole of C2H6.
Explanation:
The balanced equation for the reaction is given below:
2C2H6 + 7O2 —> 4CO2 + 6H2O
We can determine the number of mole of C2H6 that reacted to produce 2 moles of CO2 as follow:
From the balanced equation above,
2 moles of C2H6 reacted to produce 4 moles of CO2.
Therefore, Xmol of C2H6 will react to produce 2 moles of CO2 i.e
Xmol of CO2 = (2 x 2)/4
Xmol of CO2 = 1 mole.
Therefore, 1 mole of C2H6 is required to produce 2 moles of CO2.
Answer:
45.95 Jkg^-1°C^-1
Explanation:
as specific heat capacity = heat energy / mass × delta
temperature
=52500/10.2×112
=45.95 Jkg^-1°C^-1
D. They all contain carbon as an important part of their structure.
The answer is (2). Heat always flows down the temperature gradient, from high temperature to low temperature. Therefore, since the person is the warmest, heat flows from the person to both the ice and the air. Additionally, since the air is warmer than the ice, heat flows from the air to the ice.
