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lilavasa [31]
2 years ago
7

Please Help me if you can!:) i appreciate anything.

Chemistry
1 answer:
enot [183]2 years ago
7 0

Explanation:

1

Number of nucleon =

Molarmassofnucleon

Massofatom

=

1.6726×10

−24

g/nucleon

3.32×10

−23

g

=19.8=20(approximately)

It is given that element comprises of 2 atoms

Hence,number of nucleon = 2×20=40

2

You have 4.70 mol H2O

There are two H atoms in 1 molecule H2O.

Therefore, there must be 2*4.70 = 9.40 mols H in 4.70 mols H2O.

How many mols O in 4.70 mols H2O? That's 4.70 mols, of course.

Said another way, you have 2 mols H for every 1 mol H2O and 1 mol O for every 1 mol H2O.

So for 50 mols H2O you have 100 mols H and 50 mol O.

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What aqueous solution has the highest boiling point at standard pressure? A) 1.0 M KCl(aq) B) 1.0 M CaCl2(aq) C) 2.0 M KCl(aq) D
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That means that the increase in the boling point will be related to the number of particles (molecules or ions) present in the solution.


The higher the number of particles (molecules or ions) the higher the increase in the boiling point.


All the aqueous solutions presented are electrolytes, i.e. the solutes are ionic compounds.


Then, you have to compare the number of ions that you have in each solution.


A) 1.0 M KCl ---> 1.0 M K+     +      1.0 MCl-    = 2 moles of particles / liter


B) 1.0 M CaCl2 --> 1.0M Ca(2+)      +      1.0M * 2 Cl (-)    = 3 moles of particle / liter


C) 2.0M KCl ---> 2.0 M K+      +      2.0 M Cl-  = 4 moles of particle / liter


D) 2.0 M CaCl2 ----> 2.0 M Ca (2+)      + 2.0M * 2 Cl (-)  = 6 moles of particle / liter.


Then, the solution 2.0M CaCl2(aq) has the highest increase in the boiling point.


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3 years ago
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Which of the following trends can be identified on the periodic table?
Jet001 [13]

Answer:

D) atomic radii increase from top to bottom of a group

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Correct = atomic radii decreases from left to right across the period

B) ionization energy increases from top to bottom within a family

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8 0
3 years ago
Please help, I'm confused and it's due very soon!
ryzh [129]

Answer:

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2 years ago
A 10.11 g sample of NaBr contains 22.34 % Na by mass. Considering the law of constant composition (definite proportions), how ma
Ksenya-84 [330]

Answer:

1.58\ \text{g}

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