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Questions tagged [everyday-chemistry]

Applications of chemistry to reagents, reactions and processes of everyday life. Use this tag for question on chemistry in an out-of-laboratory/class context. DO NOT use this tag merely because the question is about simple chemistry.

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1answer
95 views

Is instant coffee an impurity when you add it to water? [closed]

I have this question for chemistry, but can't know whether it is an impurity or not, please help.
3
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2answers
174 views

Does hydrogen peroxide - urea become more active when illuminated?

Dentists' tooth whitening systems and consumer kits use gels containing carbamide peroxide, also known as hydrogen peroxide - urea. Dentists use a light activator: (image from Wikipedia). Consumer ...
2
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1answer
78 views

From where does sea water get salt?

I have learned that in primary classes that sea water is salty and I had also wondered that, what makes it salty? and my question is, where does sea water gets its salt?
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0answers
57 views

is rydberg constant and rydberg unit are same? [closed]

i want to ask a question that.is rydberg constant and rydberg unit are same. UNIT OF RYDBERG CONSTANT IS m^-1, right? Then what is rydberg unit.
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0answers
40 views

Are there chemicals visible with a circular polarizing lens?

I am exploring some ideas for my job and need some help. Are there any well know chemicals that are normally clear, but when viewed through a circular polarizing lens appear differently? For ...
0
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0answers
41 views

What is the significance of defining the compoud like this?

These are two definitions of a chemical compound. First, "A compound is the result of two or more elements becoming chemically combined together. The elements react chemically, causing bonds to be ...
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1answer
80 views

Electron Affinity negative? [duplicate]

Why is electron affinity negative? An electron carries energy so if we had an electron doesnt that mean we add energy? Please describe in a non-PhD lingo that a first semester chem student can ...
2
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1answer
92 views

Do I really need to wear protective clothing while using isopropyl alcohol? [closed]

I recently purchased a 500ml bottle of 99% isopropyl alcohol (aka isopropanol aka rubbing alcohol) for everyday use at home. The label for the bottle worryingly states: Wear protective gloves/...
10
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2answers
2k views

Tape versus 1922 silver coin

I have a 1922 silver half dollar with scotch tape on it. The tape has been on it 50 years plus. It’s dried out and totally adhered to the coin. I’ve soaked it in lemon essential oil and googone but ...
2
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1answer
55 views

Why does boiling oatmeal “grow”?

When cooking oatmeal (rolled oats, either long-cooking or instant) on the stove or in the microwave, when it reaches the boiling point, if left unchecked it will quickly "grow" and overflow the ...
0
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1answer
30 views

Composition of Portland Cement before Hydration [closed]

I recently came across a question- Which of following chemicals is NOT found in Portland Cement? A. Di-calcium silicate B. Tri-calcium silicate C. $\ce{CaSiO3}$ D. $\ce{Ca3(PO4)...
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1answer
102 views

Is a person warmed by fire an example of endothermic reaction? [closed]

My chemistry textbook gives the example of a man being warmed by a fire as an endothermic reaction. If the man's body is the system and it is increasing in temperature, how can this be endothermic?
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1answer
38 views

Is the mass of a mole identical for different elements? [closed]

For example, if I have 2 moles of iron and 2 moles of copper, do I have an equal mass of each?
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0answers
121 views

Gluing bakelite together

I have an older stainless steel saucepan with what I've always called a Bakelite handle. The pan fell, the handle broke. If possible, I'd like to glue it. The break is near where the handle ...
1
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1answer
28 views

Domestic cleaning products and types of solvents [closed]

I have a floor cleaner which washes and vacuums the floortiles. The instructions advise not to use solvent cleaners with it. My understanding is that even water is a solvent. The manufacturers/...
3
votes
1answer
402 views

Is teflon a poison if ingested?

Nowadays, a lot of frying pans are made with a non-stick coating. That's usually teflon, or chemically speaking polytetrafluorethylene - $\ce{(C2F4)}_n$. Can you be poisoned if some of that teflon ...
1
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0answers
99 views

Why is fluoride good for your teeth?

The main component of tooth enamel is calcium hydroxyapatite. I know fluoride ions can replace hydroxide ions in the enamel matrix, slowing the rate of enamel demineralization. Why does hydrofluoric ...
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1answer
904 views

How would you separate sodium chloride and copper sulfate?

I've tried dissolving both compounds in water and evaporating the mixture, but this leaves a combination of brown and green crystals. Is there was any way to cleanly separate both compounds? Any ...
3
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1answer
65 views

What is chemically different about tea for hard water?

At the supermarket they sold tea for hard water. (Hard water is water with limestone/calcium carbonate in it). There appears to be a chemical modification for foods using this type of water. My ...
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1answer
32 views

Dimensional Analysis [closed]

In a dimensional analysis problem they take 6.20L x (1ft^3/28.3L) x (12in^3/1ft^3) to get 378 in^3. Why do they express the 12in^3 as 12x12x12? To me it would be expressed as 6.20/28.3*12 to get 2....
1
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0answers
101 views

HCl + fingernail (set for a year) + H2O2 + Cu [closed]

I had a $\ce{HCl}$ in a container which a year ago a fingernail fell into it there were no way for me to remove it. The result of $\ce{HCl}$ and that fingernail is some brownish solution as shown: ...
3
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2answers
3k views

Can 99% isopropyl alcohol be stored in a clear container?

I'm planning to get hold of some 99% isopropyl alcohol (aka rubbing alcohol) for the purpose of cleaning electronics, and am going to transfer it from the plastic bottle it comes in to a smaller, ...
2
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1answer
104 views

Is water with oxygen-17 safe to drink? [closed]

Is it safe to drink and what else can it be used for?
43
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2answers
13k views

Why don't we explode after drinking water?

It is known that acid should be added to water and not the opposite because it results in an exothermic reaction. Our stomach contains HCl, so why don't we explode when we drink water?
5
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1answer
870 views

The chemical reaction between lemon juice and polystyrene foam cups

I have noticed that when I have lemon juice on my fingers and I touch a polystyrene foam cup (I will refrain from using the term 'styrofoam'), the cup begins to break down, i.e., melt. I can leave ...
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5answers
1k views

Is identifying a chemical equivalent to be able to produce it?

This question is a follow up of another thread, where we are discussing Theresa May's accusation of the Russian government which is supposedly behind the recent chemical attack in the UK. Soon after ...
11
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1answer
171 views

Why does automotive glass shatter into tiny pieces but glass used in our houses into shards?

Image Source : Bigstockphoto Image source : pinterest The first picture depicts the glass that is found from an accident site, while the second picture depicts the glass that we use in our home. ...
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1answer
65 views

Transesterification of vegetable oils to produce biofuels - problems in the lab

I'm an undergraduate doing a small research project on biofuels. I have 12 hours of lab time to investigate something about biofuels. I've chosen to explore how the fatty acid content of different ...
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1answer
43 views

Freezing liquid by dipping in liquid nitrogen? [closed]

It's a simple question from a chemistry-challenged person. Is it possible to pour something liquid (water, juice, etc) into a special container and dip that container into liquid nitrogen so it ...
1
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1answer
234 views

Why was my soap measured as acidic?

I've always been told soap is basic in pH. A few years back in a high school chemistry class, we measured the pH of various substances with universal pH indicator. We measured some liquid hand soap ...
0
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1answer
834 views

Why is helium used in diving apparatus?

In my textbook it said that helium is used in oxygen tanks (diving apparatus) by deep sea divers. When I searched the internet for the reason it said that : A mix of helium and oxygen is used in ...
9
votes
1answer
727 views

What chemical can cause such a fire? [closed]

A friend of mine who thinks that she is under influence of black magic met an astrologer. The astrologer asked her to wear a t-shirt for three nights and then bring that to him. The astrologer then ...
0
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0answers
29 views

Why does regular spray paint “eat” styrofoam? [duplicate]

This video demonstrates the effect and explains that The Volatile Organic Compounds in spraypaints dissolve styrofoam. I seek a more detailed explanation.
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0answers
26 views

Reaction of electromagnetic radiations with the air pollutants [closed]

My friends, who are working on an IoT based technology project, explained their idea to me which is roughly like reducing air pollution by converting pollutants to oxygen ($\ce{O2}$) in any reaction, ...
0
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0answers
683 views

Can graphite conduct electricity in molten state? [duplicate]

As metals and ionic compounds can conduct electricity in molten state, I’m wondering if graphite, being a conductor at solid state, can conduct electricity at molten state
9
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1answer
186 views

Does 95.8% silver tarnish as fast 92.5% silver?

I've been trying to find out whether 95.8% (Britannia silver) would tarnish as fast as 92.5% (Sterling silver)? I haven't been able to find much on tarnish for Britannia silver. Given that both ...
0
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0answers
721 views

Reaction of copper with lactic acid

Can Copper react with Lactic acid? Copper is a metal of low reactivity and does not displace H2 from acids. However many school texts mention reaction of copper with lactic acid to form cupric lactate ...
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1answer
83 views

Electron Energy Levels? [closed]

New to chemistry; In my book it talks about electrons in atoms moving from one energy level or shell to another and denotes this by n. How does this exactly happen, do electrons move to different ...
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1answer
36 views

Why did permanent marker come off of glass after rubbing it with my fingers?

No, my fingers don't look stained but I accidentally made a stroke of permanent marker on glass and I was looking for nail polish remover to use, couldn't find it. So I started rubbing the stroke of ...
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3answers
105 views

Question about the Law of Definite Proportions

If we know that: $1g$ of carbon + $1.33g$ of oxygen = carbon monoxide $1g$ of carbon + $2.66g$ of oxygen = carbon dioxide My question is: why is that in the second case where we doubled the amount ...
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2answers
194 views

Do all decomposition reactions involve heat? [closed]

When water decomposes into Hydrogen and Oxygen as in 2H2O—-> 2H2+O2 does this involve heat? Is it always implied that heat is involved in a decomposition reaction or does this just spontaneously occur?...
1
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1answer
1k views

Xylan vs. Teflon for non-stick food pans? [closed]

I am looking at non-stick pans and some are Xylan® others, and most, are Teflon™. What are the chemical differences? What is better for cooking? What is better for health safety? I do know that ...
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2answers
286 views

What is responsible for the odor of gasoline?

Gasoline as we know it is a blend of combustible hydrocarbons and has a characteristic odor. The natural gas we use to heat our homes and (for some of us) cook our food has its own odor, except... ...
2
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1answer
368 views

What is a suitable acid to remove limewash from masonry brick

Diluted Hydrochloric acid is often touted as the only thing to remove limewash from masonry but the process is dangerous and can adversely affect the bricks, color changes can readily occur. Is there ...
0
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1answer
67 views

What is the relation between Rate of reaction and rate of consumption of reactants?

The rate of the following reaction is 0.300M/s. What is the relative rate of change of each species in the reaction?$$\ce{A + 3B -> 2C}$$ We are supposed to find A and B and I understand that we ...
2
votes
1answer
73 views

Using drip extraction, how much caffeine is extracted from coffee as a function of the amount of water used?

When using a drip coffee maker, there are basically two choices we make: the amount of water and the amount of coffee grounds. If we use the same amount of coffee grounds but double the water, how ...
3
votes
1answer
81 views

Acetic acid odor while testing CO2 sensor; can it be easily removed, is there a better way?

A friend asked me to help test a hobby-quality $\ce{CO2}$ sensor MG-811 (updated link). It uses a solid electrolyte and should provide a sensitivity of something like -40 mV per decade. I though I'd ...
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0answers
52 views

UV-Vis and Polylactid Acid (PLA) [closed]

I am trying to use UV-VIS for a 3D printed ~4mm PLA design. However I keep running into a problem because the polymer is not showing detectable under the UV-VIS. Does anyone have any suggestions that ...
0
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1answer
47 views

What is the modern hardware/supermarket term for 'laundry bluing'?

I want to make this amazing paper Crystal Tree with my kids. One of the ingredients is laundry bluing. It is described thus: The magic crystals that are left behind are a combination of the Mrs. ...
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1answer
85 views

Separating sugar from soda

I want to do a lab with my students in which they will try to prove how much sugar is in a can of coke. I know that distillation is the go-to method for separating out the syrupy sugar mix, but does ...