Answer:
6. 7870 kg/m³ (3 s.f.)
7. 33.4 g (3 s.f.)
8. 12600 kg/m³ (3 s.f.)
Explanation:
6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.
1 kg= 1000g
1m³= 1 ×10⁶ cm³
Mass of iron bar
= 64.2g
= 64.2 ÷1000 kg
= 0.0642 kg
Volume of iron bar
= 8.16 cm³
= 8.16 ÷ 10⁶
Density of iron bar
= 7870 kg/m³ (3 s.f.)
7.
Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³
Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume
(3 s.f.)
Answer:
None
Explanation:
Cl₂ is above Br₂ in the activity series.
Bromine will not displace chlorine from its salts.
The reaction will not occur.
Answer: All of these statements are true
Explanation:
Melting point help us to determine if a mixture is pure or has impurities by the virtues of it melting range..
There are 18 protons and electrons and 22 neutrons in the atom
Answer : The final temperature of the solution in the calorimeter is, 
Explanation :
First we have to calculate the heat produced.
where,
= enthalpy change = -44.5 kJ/mol
q = heat released = ?
m = mass of 
= 1.52 g
Molar mass of = 40 g/mol
Now put all the given values in the above formula, we get:
Now we have to calculate the final temperature of solution in the calorimeter.
where,
q = heat produced = 1.691 kJ = 1691 J
m = mass of solution = 1.52 + 35.5 = 37.02 g
c = specific heat capacity of water = 
= initial temperature = 
= final temperature = ?
Now put all the given values in the above formula, we get:
Thus, the final temperature of the solution in the calorimeter is,
