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2 years ago

What was the new theory that was developed of the continental drift?

1 answer:

4 0

<span>Continental drift was a theory that explained how continents shift position on Earth's surface. Set forth in 1912 by Alfred Wegener, a geophysicist and meteorologist, continental drift also explained why look-alike animal and plant fossils, and similar rock formations, are found on different continents

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Why is titanium more expensive than iron

prohojiy [21]

Because there is less of it available.

6 0

3 years ago

Analysis of an athletes urine found the presence of a compound with a molar mass of 312 g/mol. How many moles of this compound a

rewona [7]

<h3>Answer:</h3>

= 5.79 × 10^19 molecules

<h3>Explanation:</h3>

The molar mass of the compound is 312 g/mol

Mass of the compound is 30.0 mg equivalent to 0.030 g (1 g = 1000 mg)

We are required to calculate the number of molecules present

We will use the following steps;

<h3>Step 1: Calculate the number of moles of the compound </h3>

$Moles=\frac{mass}{molar mass}$

Therefore;

Moles of the compound will be;

$=\frac{0.030}{312g/mol}$

= 9.615 × 10⁻5 mole

<h3>Step 2: Calculate the number of molecules present </h3>

Using the Avogadro's constant, 6.022 × 10^23

1 mole of a compound contains 6.022 × 10^23 molecules

Therefore;

9.615 × 10⁻5 moles of the compound will have ;

= 9.615 × 10⁻5 moles × 6.022 × 10^23 molecules

= 5.79 × 10^19 molecules

Therefore the compound contains 5.79 × 10^19 molecules

5 0

2 years ago

Which solution has the same boiling point as 0.25 mol CaCl2 dissolved in 1000 g water?

Rufina [12.5K]

The boiling point of water at 1 atm is 100 degrees celsius. However, when water is added with another substance the boiling point of it rises than when it is still a pure solvent. This called boiling point elevation, a colligative property. The equation for the boiling point elevation is expressed as the product of the ebullioscopic constant (0.52 degrees celsius / m) for water), the vant hoff factor and the concentration of solute (in terms of molality).

ΔT(CaCl2) = i x K x m = 3 x 0.52 x 0.25 = 0.39 °C
<span> ΔT(Sucrose) = 1 x 0.52 x 0.75 = 0.39 </span>°C<span>
</span><span> ΔT(Ethylene glycol) = 1 x 0.52 x 1 = 0.52 </span>°C<span>
</span><span> ΔT(CaCl2) = 3 x 0.52 x 0.50 = 0.78 </span>°C<span>
</span><span> ΔT(NaCl) = 2 x 0.52 x 0.25 = 0.26 </span>°C<span>
</span>
Thus, from the calculated values, we see that 0.75 mol sucrose dissolved on 1 kg water has the same boiling point with 0.25 mol CaCl2 dissolved in 1 kg water.

5 0

2 years ago

Oxygen and copper are examples of what?

taurus [48]

Two different elements

5 0

3 years ago

Read 2 more answers

Calculate the amount of heat needed to evaporate 235.0 grams of water from 25.0°C to 100.0°C.

steposvetlana [31]

I hope this helps answer your question. :)

These problems are very hard to do digitally so I would recommend trying to practice these types of problems on paper :)

6 0

2 years ago