Answer:
The second option
Explanation:
Check
2×2Fe = 4Fe. Both sides have 4 Fe's
2x3 O = 3x2 O Both sides have 6 O's
3x1C = 3 C Both sides have 3 C's
Ionic compounds are those compounds which are made up of ions. These ions can exist as positive or negative ions. Those ions which has tendency to lose electrons are said to be cations (positive ions) such as metals and those ions which has tendency to gain electrons are said to be anions (negative ions) such as non-metals.
The formula for ionic compounds are given as:
First, the symbols of the cation and anion should be identified. After that, charge on the cation and anion should be identified. Write the chemical formula with the help of drop and swap method.
Now,
The chemical symbols for Aluminium is 
and for chlorine is 
.
The charge on is +3 and on is -1, neglect the positive and negative signs and by using drop and swap method i.e. the charge on the aluminium will go as a subscript of the chlorine and the charge on the chlorine will go as a subscript of the aluminium which is shown in the image.
Thus, the chemical formula between and is 
.
Answer:
1,620 J.
Explanation:
- The amount of heat added to a substance (Q) can be calculated from the relation:
<em>Q = m.c.ΔT.</em>
where, Q is the amount of heat released from ethanol cooling,
m is the mass of ethanol (m = 60.0 g),
c is the specific heat of ethanol in the liquid phase, since the T is cooled below the boiling point and above the melting point (c = 1.0 J/g °C),
ΔT is the temperature difference (final T - initial T) (ΔT = 43.0 °C – 70.0 °C = - 27.0 °C).
<em>∴ Q = m.c.ΔT</em> = (60.0 g)(1.0 J/g °C)(- 27.0 °C) = - 1620 J.
<em>The system releases 1620 J.</em>
Answer:
Lungs.
Explanation:
This is because the lungs are respiratory organs in the body that are located at the either side of the thorax or chest. These are organs that are incharge of exchange of gases. The air is breathe in through the trachea i.e oxygen is inhaled and carbondioxide which is the waste product is exhaled. Gas exchange take place in the lungs.
