Answer:
This is an example of convection
Answer : The amount of heat released, -35057 J
Solution :
Process involved in the calculation of heat released :
Now we have to calculate the amount of heat released.
where,
Q = amount of heat released = ?
m = mass of water = 18 g
= specific heat of liquid water =
= enthalpy change for condensation = -40700 J/mole
Now put all the given values in the above expression, we get
Therefore, the amount of heat released, -35057 J
Answer:
Bronze is made of the metals copper and tin.
Explanation:
Bronze is stronger than copper as an outcome of combining that metal with tin or different ores. Bronze is more quickly dissolved and is hence more comfortable to cast. It is also harder than pure metal and considerably extra immune to corrosion.
Pure copper is soft and can be formed into wire or pounded into wanted shapes. If the copper is consequently warmed (tempered), it can be performed soft again. Copper and zinc are blended to create brass, and mixed with tin to produce bronze.
Answer:
a. 0.18 mol
b. 1.084 x 10²³ atoms
Explanation:
Data Given:
mass of gold (Au) = 35.12 g
a. number of moles of gold (Au) = ?
b. number of atoms of gold (Au) =?
Solution:
Part a:
To find number of moles following formula will be used
no. of moles = mass in grams / molar mass . . . . . . (1)
molar mass of gold (Au) = 197 g/mol
put values in equation 1
no. of moles = 35.12 g / 197 g/mol
no. of moles = 0.18 mol
so. number of moles of Au = 0.18 mol
_________________
Part b:
To find number of atoms following formula will be used
no. of moles = no. of atoms / Avogadro's number
Rearrange the above equation
no. of atoms = no. of moles x Avogadro's number . . . . . . . (2)
Avogadro's number = 6.022 x 10²³ atoms /mol
put values in equation 1
no. of atoms = 0.18 mol x 6.022 x 10²³
no. of atoms = 1.084 x 10²³
so.
number of atoms of Au = 1.084 x 10²³ atoms