Answer:
There were 0.00735 moles Pb^2+ in the solution
Explanation:
Step 1: Data given
Volume of the KI solution = 73.5 mL = 0.0735 L
Molarity of the KI solution = 0.200 M
Step 2: The balanced equation
2KI + Pb2+ → PbI2 + 2K+
Step 3: Calculate moles KI
moles = Molarity * volume
moles KI = 0.200M * 0.0735L = 0.0147 moles KI
Ste p 4: Calculate moles Pb^2+
For 2 moles KI we need 1 mol Pb^2+ to produce 1 mol PbI2 and 2 moles K+
For 0.0147 moles KI we need 0.0147 / 2 = 0.00735 moles Pb^2+
There were 0.00735 moles Pb^2+ in the solution
Answer:
1)They breathe to air
2)They need nutrition to live
3)Their body is made up of cells
4)All living things respond to stimuli.
Explanation:
Answer:
1.09 × 10⁻⁷ m
UV region
Explanation:
Step 1: Given and required data
Energy of the photon of light (E): 1.83 × 10⁻¹⁸ J
Planck's constant (h): 6.63 × 10⁻³⁴ J.s
Speed of light (c): 3.00 × 10⁸ m/s
Step 2: Calculate the wavelength (λ) of this photon of light
We will use the Planck-Einstein's relation.
E = h × c/λ
λ = h × c/E
λ = 6.63 × 10⁻³⁴ J.s × (3.00 × 10⁸ m/s)/1.83 × 10⁻¹⁸ J = 1.09 × 10⁻⁷ m
This wavelenght falls in the UV region of the electromagnetic spectrum.
Answer:
subscript is 3
Explanation:
the subscript is the number that is slightly lower than a # which in this case it's O
this indicates that there's 3 oxygen atoms
