Answer:
1.28 mol NaCl
Explanation:
Find the mass of NaCl by adding the two elements atomic mass
Na: 22.99
Cl: 35.45
22.99+35.45=58.44 g
Now convert to moles
74.8 g / 58.44 g = 1.27994524298 mol
Jewelry and tableware are sometimes made of sterling silver. Sterling silver is 92.5% silver (Ag) and 7.5% copper (Cu). If you wanted to make 30 grams of sterling silver for a ring, how many grams of silver and copper would you need to start with?
Amount of sterling silver?
Amount of copper?
total grams of alloys needed?
Answer:
12.33
Explanation:
92.5/7.5= 12.33
30g of the sterling silver ring contains, 27.75 g of silver and 2.25 g of copper.
What is cross multiplication?Cross multiply fractions by multiplying one fraction's denominator by the other fraction's numerator and then comparing the two values. The larger fraction is the one with the higher value.
100g of sterling silver contains 92.5g of silver and 7.5g of copper.percentage of element = amount of the element present in 100 g of materialTherefore,
100g sterling silver = 92.5g silver30g sterling silver = X g silver( cross multiplication),
100 × X = 92.5 × 30
X = 92.5 × 30/ 100
X= 27.75g silver100g sterling silver = 7.5g copper
30g sterling silver= Y g copper
(cross multiply)
100 × Y = 7.5 × 30
Y= 7.5 × 30 / 100
Y= 2.25g copperX (silver)= 27.75 g in 30 g of sterling silverY (copper)= 2.25 g in 30 g of sterling silvertherefore, 30g of sterling silver ring contains, 27.75 g of silver and 2.25 g of copper.
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why are oxidation numbers assigned to the elements before writing a chemical formula
Answer:
Oxidation numbers assign ownership of the electrons to one atom or another in a compound. ... Scientists use these numbers to help name compounds, write formulas and balance chemical equations. They are also useful when studying reactions and they can help you identify when something is oxidized or reduced.
Chemical reactions happen when _____. a.atoms attract or repel one another b.heat is created by friction c. two or more substances are mixed substances are heated or d.cooled
Answer:
A
Explanation:
How many moles are there in 1.20 x 1025 particles of helium?
Answer:
You would get 19.969 moles.
Explanation:
You would get 19.969 moles.
The energy associated with a current is called____________
(A) mechanical energy
(B) magnetism
(C) geothermal energy
(D) electrical energy
Answer:
D. Electrical energy
Explanation:
I assume you are talking about an electrical current.
(These are by what I know and are simplified, not an exact definition)
A. Mechanical energy is energy that something has because of motion.
B. Magnetism is the attracting and repulsing forces between magnets.
C. Geothermal energy is heat inside of the Earth. Used as source of power.
D. Electrical energy is the result of an electric charge.
How many moles are contained in 7.88 x 10^24 atoms of Iron
Answer:
1.31 × 10^47
Explanation:
1 mol of Fe =
[tex]1 \: mol \: of \ fe = 6.02 \times 10 ^{23} \ \\ x \: mol \: offe \: = 7.88 \times {10}^{24} \\ \\ \\ so \: 7.88 \times {10}^{24} \div 6.02 \times {10}^{23} \\ \\ x = 1.31 \times {10}^{47} [/tex]
An artificial reef is intended to affect the ocean ecosystem by — А A removing pollution from the water B В providing shelter for marine organisms causing sediment to erode into deeper waters D preventing people from overfishing along the shore
Answer:
B
Explanation:
just answered
An artificial reef is intended to affect the ocean ecosystem by providing shelter and habitat for marine organisms causing sediment to erode into deeper waters. Hence, option C is correct.
What is artificial reef ?An artificial reef is a human-made underwater structure, typically constructed with the purpose of enhancing marine biodiversity, providing habitat for marine organisms, and promoting recreational activities like fishing, diving, and snorkeling.
Artificial reefs can be created from a variety of materials, such as concrete, metal, tires, and sunken ships. The reef structure can also increase the overall biodiversity of an area by creating a new habitat for species that may not have been present before.
Additionally, the presence of an artificial reef can help to reduce pressure on natural reefs by providing an alternative location for fishing and other activities. However, artificial reefs are not typically used as a means of removing pollution from the water or preventing erosion.
Therefore, option C is correct.
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Calculate ΔGo if the equilibrium constant is 1.37 x 10-5
Explanation:
your answer willing be 8.7
Can someone help me over here? I need an negative charge and also another thing is that in a question it asked me to use something that would represent an ion. I’m not sure on what to choose either Hydrogen or Helium but just please send help.
Answer:
You could use a hydrogen anion which has 2 electrons.
Explanation:
An ion is an atom or molecule with a net electric charge because it has more or less electrons compared to the original atom or molecule.
An anion is a negatively charged ion.
A cation is a positively charged ion.
Normally a hydrogen atom has one proton and one electron.
So a hydrogen anion (H-) means that it has one proton and two electrons, which means the positive charge will be +1 and the negative charge will be -2.
Ultimately, giving the entire molecule a net charge of -1 because -2+1 = -1.
(I hope this helps! I am not 100% sure what's the format of this question. Like is it interactive? online? Did you draw all those electrons on the diagram? or were they given? Are the numbers given as well? or did you type those in? So I just tried my best to give you something that might work.)
How many atoms is 45 moles of silicon (Si)?
how does bases taste?
Answer:
bases taste bitter, feel slippery, and conduct electricity when dissolved in water
Explanation:
Answer:
like peas
Explanation:
pls help
Plot the point (5,9)
In a graph, what effect would adding a catalyst have on D?
A. It would decrease.
B. It would increase.
C. It would stay the same.
D. You cannot tell from this graph.
Answer:
C. It would stay the same
Explanation:
PLATO answer
13. What is the meaning of the word faint?
 how are subscripts determine the formula of ionic and covalent compounds ?
Answer:
To determine the correct subscripts in a chemical formula, you have to solve how many atoms you need to balance the charge.
For example if I had the compound Calcium Fluoride I would look at the periodic table and see that Calcium's ionic formula is
Ca2+
. How do I know this? Well all elements want to have 8 valance electrons so they can be stable(happy). Seeing that Calcium has 2 valance electrons it is going to give away 2 electrons because that is easier than gaining 6 to be happy. Since Calcium has given away 2 electrons it has two more protons than electrons. We know that Protons have a Positive charge, Electrons have Negative charge, and the number of electrons is equal to the atomic number of an element in its pure non-ionic state. (Meaning it doesn't have a positive or negative charge; it is balanced.)
So if calcium gave away two electrons, it will have two more protons than an electron giving it a (2+) charge. The same process can be applied to Fluoride. Since fluoride is one to the left of the noble gases(group 18 or 8A) on the periodic table we know that it has 7 valance electrons because it is in group 7A or 17.
Knowing that we have 7 electrons the fluoride atom will gain an extra electron. Since the fluoride atom gained an extra electron it will have one more negative charge than a positive making it a ^(−)ion.
So you know that Calcium has a 2+ charge and that fluoride has a 1- charge, you then need these ions to balance out. So you need two fluorine atoms with a 1- ions to balance out the 2+ ion of calcium. Your final answer would be
CaF2
because you need two fluorine atoms to balance out the 2+ charge of the calcium.
Final Tip: Determine the charges then inverse the charges, remove the positive and negative superscipts, and write the charge numbers as a sub script. Ie. Calcium Fluoride
Ca2+ and F−
inversing and removing the charge signs would give you
True or False:
Houston, Texas received approximately 2 inches of snow on February 15, 2021. Based on this, we can now say Houston's climate consists of long, freezing winters and yearly snowfall. Please answer ASAP. Thanks
Answer:
False.
Explanation:
I majored in Chemistry
Pls help I’ll mark brainliest pls pls pls
Answer:
the tea was not hot sugar dissolves quickly and hot water than cold
Hypothesis: What do you think will happen when you add more magnets to the set up?
Answer:
........................
Which name for an ionic compound is
incorrect?
Chromium(IID fluoride (for CrF3 )
Copper(ID) oxide (for Cuo)
Potassium(I bromide (for KBr)
Answer:
no se ingles todavía no aprendo a hablar inglés ya si estuvieran en español los respondia