Which will dissolve faster in water one gram cube of sugar or one gram of powder sugar?

Explain how you would decide which represents a greater mass: 3.25 x 1022 atoms of Ca or 2.45 grams of Mg?

elena55 [62]

Answer:

<u>You need to convert the number of atoms of Ca into mass in grams, using Avogadro's number and the atomic mass of Ca.</u>

Explanation:

The amount of matter is measured in grams. Thus, you need to convert the number of atoms of Ca (calcium) into mass to compare with 2.45 grams of Mg.

To convert the atoms of calcium into mass, you divide by Avogadro's number, to obtain the number of moles of atoms, and then divide by the atomic mass of calcium.

<u />

<u>1. Number of moles, n</u>

$n=\dfrac{\text{number of atoms}}{\text{Avogadro's number}}\\ \\ \\ n=\dfrac{3.25\times 10^{22}}{6.022\times 10^{23}}=0.053969mol$

<u />

mass = number of moles × atomic mass

mass = 0.053969mol × 40.078g/mol = 2.16g

Then, 2.45 g of Mg represent a greaer mass than the 3.25 × 10²² atoms of Ca.

4 0

3 years ago

E)¿Cuántos átomos de oxigeno hay en la molécula de glucosa, al reaccionar 12moleculas de agua?

elena55 [62]

Answer:

12 átomos de oxígeno hay presentes

Explanation:

Basados en la reacción:

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

<em>6 moles de agua producen 1 mol de glucosa</em>

<em />

Si reaccionan 12 moleculas de agua, se producirán:

12 moleculas H₂O * (1 mol C₆H₁₂O₆ / 6 mol H₂O) =

2 moléculas de glucosa se producen.

Como cada molécula de glucosa tiene 6 átomos de oxígeno:

2 moléculas C₆H₁₂O₆ * (6 átomos Oxígeno / 1 molécula C₆H₁₂O₆) =

<h3>12 átomos de oxígeno hay presentes</h3>

6 0

3 years ago

3. How many molecules are in 2.10 moles of H2O?

AnnZ [28]

Answer:

<h2>1.264 × 10²⁴ molecules</h2>

Explanation:

The number of molecules can be found by using the formula

N = n × L

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

N = 2.10 × 6.02 × 10²³

We have the final answer as

<h3>1.264 × 10²⁴ molecules</h3>

Hope this helps you

5 0

3 years ago

"The statements in the following multiple choices deal with various aspects of the relationship between vapor pressure and inter

solong [7]

Answer:

Explanation:

a ) false.

NH₃ is more polar molecule than PH₃ so inter-molucular attraction is greater in NH₃ ( hydrogen bond ) . Hence vapour pressure is low for NH₃ .

b ) false .

The average kinetic energy of boiling water molecules is lower on a mountaintop than it is at sea level. It is so because water boils at lower temperture on mountain and kinetic energy of molecules depends upon temperature .

c ) false

vapour pressure depends upon temperature .

d ) True

CCl4 is more volatile than CBr4

e ) false

vapour pressure increases as temperature increases.

8 0

3 years ago

Write balanced chemical equation for the reactions used to prepare each of the following compounds from the given starting mater

creativ13 [48]

Explanation:

A balanced chemical equation is defined as the one that contains same number of atoms on both reactant and product side.

Whereas a chemical reaction that brings change in oxidation state of the reacting species is known as a redox reaction.

When there occurs decrease in oxidation number of an element then it shows the element has been reduced. And, if there occurs an increase in oxidation state of an element then it means the element has been oxidized.

(a) The reaction between nitrogen and hydrogen to form ammonia will be as follows.

$N_{2} + 3H_{2} \rightarrow 2NH_{3}$

So here, oxidation state of nitrogen is changing from 0 to -3. Whereas oxidation state of hydrogen is changing from 0 to +3.

Reaction between ammonia and nitric acid will be as follows.

$NH_{3} + HNO_{3} \rightarrow NH_{4}NO_{3}$

Since, it is a combination reaction. Therefore, no change in oxidation state of reacting species is taking place.

(b) Reaction for conversion of liquid bromine to hydrogen bromide is as follows.

$H_{2}(g) + Br_{2}(l) \rightarrow 2HBr(g)$

Here, oxidation state of hydrogen is changing from 0 to +1. Therefore, oxidation of hydrogen is taking place. On the other hand, oxidation state of bromine is changing from zero to -1. Therefore, reduction of bromine is taking place.

(c) Reaction between Zn and S will be as follows.

$Zn(s) + S(s) \rightarrow ZnS(s)$

Here, oxidation state of zinc is changing from 0 to +2. Hence, oxidation of zinc is taking place.

Oxidation state of sulfur is changing from 0 to -2. Therefore, reduction of sulfur is taking place.

7 0

3 years ago