Answer:
when the forward and reverse reactions occur at equal rates.
chemical reaction is in equilibrium when the concentrations of reactants and products are constant - their ratio does not vary.
Answer:
d = 0.93 g/cm³
Explanation:
Given data:
Mass of object = 28 g
Volume of object = 3cm×2cm×5cm
density of object = ?
Solution:
Volume of object = 3cm × 2cm ×5cm
Volume of object = 30 cm³
Density of object:
d = m/v
by putting values,
d = 28 g/ 30 cm³
d = 0.93 g/cm³
Mass of methanol (CH3OH) = 1.922 g
Change in Temperature (t) = 4.20°C
Heat capacity of the bomb plus water = 10.4 KJ/oC
The heat absorbed by the bomb and water is equal to the product of the heat capacity and the temperature change.
Let’s assume that no heat is lost to the surroundings. First, let’s calculate the heat changes in the calorimeter. This is calculated using the formula shown below:
qcal = Ccalt
Where, qcal = heat of reaction
Ccal = heat capacity of calorimeter
t = change in temperature of the sample
Now, let’s calculate qcal:
qcal = (10.4 kJ/°C)(4.20°C)
= 43.68 kJ
Always qsys = qcal + qrxn = 0,
qrxn = -43.68 kJ
The heat change of the reaction is - 43.68 kJ which is the heat released by the combustion of 1.922 g of CH3OH. Therefore, the conversion factor is:
Answer : The mass in grams of calcium sulfate is 0.16 grams.
Explanation :
Molarity : It is defined as the number of moles of solute present in one litre of solution.
Formula used :
Solute is, 
Given:
Molarity of = 0.0025 mol/L
Molar mass of = 136 g/mole
Volume of solution = 485 mL
Now put all the given values in the above formula, we get:
Thus, the mass in grams of calcium sulfate is 0.16 grams.
Answer:
14.4g
Explanation:
First, we need to write a balanced equation for the reaction between Fe and O2 to produce Fe2O3. This is illustrated below:
4Fe + 3O2 —> 2Fe2O3
From the balanced equation,
4moles of Fe produced 2moles of Fe2O3.
Therefore, 0.18mol of Fe will produce = (0.18x2) /4 = 0.09mol of Fe2O3.
Now we need to find the mass present in 0.09mol of Fe2O3. This can be achieved by doing the following:
Molar Mass of Fe2O3 = (56x2) + (16x3) = 112 + 48 = 160g/mol
Number of mole of Fe2O3 = 0.09mol
Number of mole = Mass /Molar Mass
Mass = number of mole x molar Mass
Mass of Fe2O3 = 0.09 x 160 = 14.4g
