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2 years ago

What is an investigation that is controlled

Chemistry

1 answer:

Ivan2 years ago

7 0

A controlled investigation is a experiment that is set for example the same rule for everything
Hope this helps

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a radiator is filled with a mixture of 3.25kg ethylene glycol (C2H6O2) in 7.75kg of water. calculate the molality of this questi

Vladimir [108]

3.25 kg in g = 3.25 * 1000 = 3250 g

Molar mass C₂H₆O₂ = 62.0 g/mol

Mass solvent = 7.75 kg

Number of moles:

n = mass solute / molar mass

n = 3250 / 62.0

n = 52.419 moles

Molality = moles of solute / kilograms of solvent

M = 52.419 / 7.75

M = 6.7637 mol/kg

hope this helps!

5 0

3 years ago

Historically the troubadour was a ____.

eimsori [14]

Composer and performer of Old Occitan lyric poetryduring the High Middle Ages (1100–1350). Since the word troubadour is etymologically masculine, a female troubadour is usually called a trobairitz.

6 0

3 years ago

Explain why vegetables last longer in a fridge.

jeka57 [31]

It has to do with the releasing of ethylene, which speeds up the ripening process

6 0

2 years ago

Read 2 more answers

Naturally occurring element X exists in three isotopic forms: X-28 (27.979 amu, 92.21% abundance), X-29 (28.976 amu 4.70% abunda

bezimeni [28]

Answer: The average atomic mass of X is 28.09 amu

Explanation:

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$ .....(1)

For isotope 1:

Mass of isotope 1 = 27.979 amu

Percentage abundance of isotope 1 = 92.21 %

Fractional abundance of isotope 1 = 0.9212

For isotope 2:

Mass of isotope 2 = 28.976 amu

Percentage abundance of isotope 2 = 4.70 %

Fractional abundance of isotope 2 = 0.0470

For isotope 3:

Mass of isotope 3 = 29.974 amu

Percentage abundance of isotope 3 = 3.09 %

Fractional abundance of isotope 3 = 0.0309

Putting values in equation 1, we get:

$\text{Average atomic mass of X}=[(27.979\times 0.9212)+(28.976\times 0.0470)+(29.974\times 0.0309)]$

$\text{Average atomic mass of X}=28.09amu$

Hence, the average atomic mass of X is 28.09 amu

4 0

3 years ago

Balance the following equation: K+ H2O + H2 + KOH

alex41 [277]

Answer:

2K + 2H2O → H2 + 2KOH

Explanation:

Find how many atoms you have on both sides then add 2 to both sides.

Reactant: Products:

K: 1+1=2 K: 1+1=2

H: 2+2=4 H: 3+1=4

O: 1+1=2 O: 1+1=2

Therefore it is balanced. Hope this helps

6 0

2 years ago