Answer:
A- beryllium
B- calcium
C- magnesium
Explanation
NOTE: all element in group 2 have 2 balance electrons
First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20
C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).
A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.
<u>Answer:</u> The partial pressure of carbon dioxide at equilibrium is 0.0056 atm
<u>Explanation:</u>
The given chemical equation follows:

<u>Initial:</u> 4.00
<u>At eqllm:</u> 4.00-2x x x
The expression of
for above reaction follows:

The partial pressure of pure solids and liquids are taken as 1 in the equilibrium constant expression.
We are given:

Putting values in above expression, we get:

Neglecting the value of x = 718.28 because equilibrium pressure cannot be greater than initial pressure
Partial pressure of
= 0.0056 atm
Hence, the partial pressure of carbon dioxide at equilibrium is 0.0056 atm
Questions:
The questions or computes to do are:
<span>a- a massa, em
kg, de cada placa de alumínio;
b- a quantidade mínima de viagens
necessárias para que apenas um veículo de transporte entregue o material
solicitado ao cliente.
Dado: densidade do alumínio = 2,7 g/cm3
Answer:
a) mass in kg of every aluminum plate
Dimensions of every aluminum plate: </span>
<span>2 M X 50 Cm X 2cm
Volume: 200 cm * 50 cm * 2 cm = 20,000 cm^3
Mass:
density = mass / volume => mass = density * volume = 2.7 g/cm^3 * 20,000 cm^3 = 54,000 g = 54 kg.
Answer: the mass of everyplate of aluminum is 54 kg.
b) number of travels required for one truck deliver all the material:
number of travels = amount requested / amount that a truck can deliver in one travel.
amount requested: 100 plates
mass of 100 plates = 100 plates * 54 kg / plate = 5,400 kg
limit of transport per travel: 3 tons = 3,000 kg
number of travels = 5,400 kg / 3,000 kg/travel = 1.8 travels => 2 travels.
Answer: at least 2 travels.
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