The unknown substance : Lead
<h3>Further explanation</h3>
Given
Density of element
mass of unknown substance = 40 g
volume = 3.5 cm³
Required
The density of unknown substance
Solution
Density is the ratio of mass per unit volume
The unit of density can be expressed in g/cm³ or kg/m³
Density formula:
Input the value to find the density of an unknown substance :
ρ = 40 g : 3.5 cm³
ρ = 11.43 g/cm³
If we look at the table, the substance which has a density of 11.43 is Lead
Answer:
the ander is B. 6 neurons
Answer:
Kp = 1.41 x 10⁻⁶
Explanation:
We have the chemical equation:
2 A(g) + 3 B(g)⇌ C(g)
In which A and B are the reactants and C is the product. We calculate first the change in the number of moles of gas (Δn or dn):
dn= (sum moles products - sum moles reactants)
= (moles C - (moles A + moles B))
= (1 - (2+3))
= 1 - 5
= -4
We have also the following data:
Kc = 63.2
T= 81∘C + 273 = 354 K
R = 0.082 L.atm/K.mol (it is a constant)
Thus, we introduce the data in the mathematical expression for the relation between Kp and Kc:
= (0.082 L.atm/K.mol x 354 K)⁻⁴ = 1.41 x 10⁻⁶
Answer:
For number 5 it is the 2nd one some stants has a mass of 1.25 g And the 2nd 1 number 6It is the 1st 1A subject has a melting point of 40