Answer:
In 1851 gold-seekers from around the world began pouring into the colonies, changing the course of Australian history. The gold rushes greatly expanded Australia's population, boosted its economy, and led to the emergence of a new national identity.
Explanation:
Answer:
A. Metalloid
E. Has similar properties as Ge
F. Belongs to Period 3
Explanation:
Silicon is the 14th element on the periodic table. Its unit is SI. Its properties straddles between those of metals and non-metals and it is described as a non-metal.
It's atomic weight or mass number is 28u. It has an atomic number of 14 i.e in its neutral state, the number of protons and electrons are equal to 14.
Silicon belongs to the 4th group and the 3rd period on the periodic table. Elements in the same group share similar chemical properties. The elements in Si group are: C, Ge, Sn and Pb. The properties of Si is similar to these elements because they all have a valency of 4. Across the period, the properties varies this is why Si would have a very different property from Al and P.
Answer:
<h2>81.5 g</h2>
Explanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volume
From the question we have
mass = 25 × 3.26
We have the final answer as
<h3>81.5 g</h3>
Hope this helps you
Answer:
333.7 g.
Explanation:
- The depression in freezing point of water (ΔTf) due to adding a solute to it is given by: <em>ΔTf = Kf.m.</em>
Where, ΔTf is the depression in water freezing point (ΔTf = 20.0°C).
Kf is the molal freezing point depression constant of the solvent (Kf = 1.86 °C/m).
m is the molality of the solution.
<em>∴ m = ΔTf/Kf</em> = (20.0°C)/(1.86 °C/m) = <em>10.75 m.</em>
molaity (m) is the no. of moles of solute per kg of the solvent.
∵ m = (no. of moles of antifreeze C₂H₄(OH)₂)/(mass of water (kg))
∴ no. of moles of antifreeze C₂H₄(OH)₂ = (m)(mass of water (kg)) = (10.75 m)(0.5 kg) = 5.376 mol.
∵ no. of moles = mass/molar mass.
<em>∴ mass of antifreeze C₂H₄(OH)₂ = no. of moles x molar mass </em>= (5.376 mol)(62.07 g/mol) =<em> 333.7 g.</em>
