7.91 g/ml is the density of the iron piece of 28.5 gms.
Explanation:
The density of a substance is defined as the volume it occupies. It tells the matter present in a substance.
The density is mass per unit volume and is denoted by p.
The formula for density is given by:
density (p) = 
Data given is :
mass= 28.5 grams
V1 = 45.5 ml
V2= 49.1 ml
The initial volume of water was 45.5 ml, when iron piece of 28.5 grams was added the final volume was 49.1 ml.
Putting the values in the equation of density
p = 
p = 7.91 g/ml
Since iron is a dense material it will occupy less volume
PbSO₄ partially dissociates in water. the balanced equation is;
PbSO₄(s) ⇄ Pb²⁺(aq) + SO₄²⁻(aq)
Initial - -
Change -X +X +X
Equilibrium X X
Ksp = [Pb²⁺(aq)] [SO₄²⁻(aq)]
1.6 x 10⁻⁸ = X * X
1.6 x 10⁻⁸ = X²
X = 1.3 x 10⁻⁴ M
Hence the Pb²⁺ concentration in underground water is 1.3 x 10⁻⁴ M.
[Pb²⁺] = 1.3 x 10⁻⁴ M.
= 1.3 x 10⁻⁴ mol / L x 207 g / mol
= 26.91 ppm
Answer : The type of reaction described in the sentence is Synthesis or Combination
Explanation :
The balanced equation for the reaction between Phosphorous and Oxygen gas can be written as
From the above equation we can see that there are two different reactants ( P and O₂ ) which are combining with each other to give a single product.
This type of reaction is known as Combination or Synthesis.
A general form of Synthesis reaction is given below.
Here we can conclude that a synthesis / combination reaction is the one where 2 or more reactants combine together to give only one product .
Answer:
See explanation and image attached
Explanation:
The standard cell potential at 298 K is given by;
E°cathode - E°anode
Hence;
E°cell = 0.34 V - (-0.76 V)
E°cell = 0.34 V + 0.76 V
E°cell = 1.1 V
To reduce Zn^2+ to Zn then Zn must be the cathode, hence;
E°cell = (-0.76 V) - 0.34 V
E°cell = -1.1 V
<u>Answer:</u> The final volume of the gas comes out to be 4 L.
<u>Explanation:</u>
To calculate the volume with changing pressure, we use the equation given by Boyle's law.
This law states that pressure is inversely proportional to the volume of the gas at constant temperature and number of moles.
Mathematically,
(At constant temperature and number of moles)
The equation given by this law is:
where,
are initial pressure and volume.
are final pressure and volume.
We are given:
Putting values in above equation, we get:
Hence, the final volume of the gas will be 4 L.
