1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ivolga24 [154]
3 years ago
6

A student attempted to identify an unknown compound by the method used in the experiment. She found that when she heated the sam

ple weighing 0.4862g, the mass barely changed, dropping to 0.4855g. When the product was converted to a chloride, the mass went up to 0.5247g. Is the sample a carbonate? What are the two compounds that might be the unknown?
Chemistry
2 answers:
Brrunno [24]3 years ago
6 0

Answer:

The sample is a carbonate.

The unknown samples are Na2CO3 and K2CO3.

Explanation:

Let's assume ,the sample is Na2CO3.

Na2CO3 produces 2 moles of NaCl via formation of Na2O

Number of moles of NaCO3= 0.48262g/106gmol= 4.586×10^-3mol

Mass of NaCl= 2(4.586×10^-3)×58.5=0.536g

Let's assume the sample is K2CO3

K2CO3 produces2 moles of KCl

Number of moles of K2CO3= 0.4862g/138.21gmol

Number of moles= 3.517×10^-3mol

Mass of KCl formed= 2(3.517×10^-3)×74.55=0.5246g

yanalaym [24]3 years ago
3 0
Na2CO3 + 2Cl- ⇒ 2NaCl + CO3^-2 
<span>
1 mole of Na2CO3 = 106 g </span>
<span>2 moles of NaCl     = 2 x 58.4
                               = 116.8 g 
</span>Na2CO3 would increase by 116.8 / 106 = 1.10 to form 2NaCl.
<span>0.4862 g x 1.10 = 0.515 grams of NaCl.
</span>
K2CO3 + 2Cl- ⇒ 2KCl + CO3^-2 
<span>1 mole of K2CO3 = 138.2 g </span>
<span>2 moles of KCl = 149.1 </span>
<span>
K2CO3 would increase by </span>149.1 /138.2 = 1.079 <span>to form 2KCl
</span>
<span> 0.4862 x 1.079 = 0.5246 g</span>


You might be interested in
What is one effect of the Gulf Stream
skad [1K]

Answer:

This strong current of warm water influences the climate of the east coast of Florida, keeping temperatures there warmer in the winter and cooler in the summer than the other southeastern states. Since the Gulf Stream also extends toward Europe, it warms western European countries as well.

5 0
3 years ago
Read 2 more answers
A helium balloon with a volume of 5.0 L and a pressure of 105 kPa at 25°C floats up high in the sky where the pressure is 850 mm
aalyn [17]

Answer:

volume 2-     4.011 L

8 0
3 years ago
What is the density of object A? Does it sink<br> or float in water?
Oksana_A [137]

Answer:

~1.5 g/cm3 and it does NOT float in water.

Explanation:

If you look at the graph, Object A weighs ~6 grams and is ~4 cm3 in volume

Density = Mass/Volume

So 6 grams/4 cm3 = 1.5 g/cm3

Water has a density of 1 g/cm3 and because Object A density is higher than that of water, it sinks.

:)

3 0
3 years ago
Why is red the last color seen at sunset?
Dimas [21]
Within the visible range of light, red<span> light waves are scattered the least by atmospheric gas molecules. So at sunrise and </span>sunset, when the sunlight travels a long path through the atmosphere to reach our eyes, the blue light has been mostly removed, leaving mostly red<span> and yellow light remaining.</span>
8 0
3 years ago
Calculate the ph of a solution in which [oh–] = 4.5 × 10–9m.
frosja888 [35]

pOH = -LOG([OH])  

pOH = -LOG(4.5*10^-9)  

pOH = 8.34  

pH + pOH = 14  

pH = 14 - 8.34 = 5.65

hope this helps!

(:

5 0
3 years ago
Other questions:
  • Convert 32.56 km/hr into ft/hr
    12·1 answer
  • How do you find the number of valence electrons
    10·2 answers
  • What do these two changes have in common?
    12·1 answer
  • How are radio waves transmitted
    7·1 answer
  • N2 (g) + 2O2(g) = 2NO2 (g) ΔH = 66.4 kJ 2NO (g) + O2 (g) = 2NO2 (g) ΔH = -114.2 kJ the enthalpy of the reaction of the nitrogen
    7·2 answers
  • What is a plateau and how can one form?
    13·2 answers
  • Kahdbiaddsk;wvfodas vs;oi vsd;iv sdv;sidv s;vowdbvw;dichvbwdv;iwebfwd;iwdbcv;wkfbsdliasbv;soqivbasd
    13·2 answers
  • The graph shows the distance an object travel in 11 seconds which answer choice best describes the movement of the object betwee
    15·1 answer
  • If the point of the nail can be approximated as a circle with a radius 2.00×10^-3m What is the pressure in MPa exerted on the wa
    15·1 answer
  • Calculate the number of grams nitric acid (HNO3) in 375 L of a 1.00 M solution.
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!