Answer:
T2 = 29°C
Explanation:
Given data:
Heat added = 420 j
Mass of water = 25 g
Initial temperature = 25°C
Final temperature = ?
Solution;
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Specific heat capacity of water = 4.18 j/g.°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
Now we will put the values.
420 j = 25 g ×4.18 j/g.°C × (Final temperature - initial temperature)
420 j = 25 g ×4.18 j/g.°C × (T2 - 25°C)
420 j = 104.5 j/°C × (T2 - 25°C)
420 j /104.5 j/°C = T2 - 25°C
4°C + 25°C = T2
T2 = 29°C
10 = 50
30 = 86
40 = 104
37 = 98.6
0 = 32
Mixtures <span>are not chemically united, so they can be divided using physical methods.
</span>Sand is a <span>mixture. (Because different rocks have different chemical compositions.)</span>
Explanation:
When designing and conducting a scientific experiment then it is necessary to sequentially follows all the steps necessary for the experiment.
Also, it is required to identify independent variables, if any. On the other hand, it is required to address any confounding variables, so that it becomes mentioned the type or number of variables present.
Thus, we can conclude that when designing and conducting a scientific experiment:
- Identify the independent variable.
- Address any confounding variables.
Answer: B. you will need 53.2 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number of particles.
To calculate the moles, we use the equation:
The balanced reaction is:
2 moles of aluminium react with= 3 moles of chlorine
Thus 0.5 moles of aluminium react with= moles of chlorine
Mass of chlorine=
2 moles of aluminium produce = 2 moles of aluminium chloride
Thus 0.5 moles of aluminium react with= moles of aluminium chloride
Mass of aluminium chloride=
Thus 53.2 g of chlorine is used and 66.7 g of aluminium chloride is produced.