Answer:
1. SUBSTANCE A IS SOLUBLE IN WATER WHILE SUBSTANCE B IS INSOLUBLE IN WATER.
Looking at the information given in the question about the two substance, you will discover that 60 g of both substances were initially put in the beaker. While the mass of undissolved substance for substance A is variable, that of substance B remain constant at 60 g, this shows that the substance is not soluble in water.
2. Looking at the two substances given in the question, you will observe that for substance A, the degree of solubility in water decreases as the temperature of the water increases. For instance, at 20 degree Celsius, the mass of undissolved substance is 5 and as the temperature increases to 40, 60 and 80 degree Celsius, the mass of undissolved substances also increase to 10, 14 and 18 respectively. This shows that, the higher the temperature, the less of the substance will dissolve. For substance B, the mass of undissolved substance remain constant at all temperatures, which shows that the substance is insoluble in water. Thus, the data given helps to determine the solubility of the substance by giving the amount of substances that are insoluble at each temperature.
Explanation:
The half-life of Th-227 is 18.2 day. How many days are required for 0.70g of a given sample
to decay to 0.04375 g?
Answer:
73 days
Explanation:
From the question given above, the following data were obtained:
Half life (t½) = 18.2 day.
Original amount (N₀) = 0.70 g
Amount remaining (N) = 0.04375 g
Time (t) =.?
Next, we shall determine the rate of decay of the isotope. This can be obtained as follow:
Half life (t½) = 18.2 day.
Decay constant (K) =.?
K = 0.693 / t½
K = 0.693 / 18.2
K = 0.038 /day
Finally, we shall determine the time taken for the isotope to decay to 0.04375 g. This can be obtained as follow:
Original amount (N₀) = 0.70 g
Amount remaining (N) = 0.04375 g
Decay constant (K) = 0.038 /day
Time (t) =.?
Log(N₀/N) = kt /2.303
Log (0.70/0.04375) = (0.038 × t) /2.303
Log 16 = (0.038 × t) /2.303
1.2041 = (0.038 × t) /2.303
Cross multiply
1.2041 × 2.303 = 0.038 × t
Divide both side 0.038
t = (1.2041 × 2.303) / 0.038
t = 72.97 ≈ 73 days
Therefore, it will take approximately 73 days for the isotope to decay to 0.04375 g
What group will elements in the 7th column bond to?
1. Which of the following substances are elements?
(a) bronze
(b) tin
(c) chromium
(d) solder
(e) propane
(1) arsenic
(g) nickel
The mass spectrum of the element Sb is most likely represented by which of the following?
A. 122 Atomic Mass
B. 121 and 123 Atomic Mass
C. 120, 123 and 124 Atomic Mass
D. 120,121 and 124 Atomic Mass
The correct answer is B: 121 and 123 Atomic Mass.
Mass spectrometers only detect stable isotopes.
Almost all elements exhibit isotopy. Isotopy is a phenomenon whereby atoms of the same atomic number have different atomic masses. The relative atomic mass of each element is the weighted average of the masses of all its isotopes.
Owing to the phenomenon of isotopy, the relative atomic mass of elements are not whole numbers.
The isotopes recorded by a mass spectrometer are stable isotopes of an element. The two stable isotopes of antimony are Sb-121 and Sb-123. These two appear in its mass spectrum.
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Why do nonmetals have a higher electronegativity?
Answer:
Nonmetals have more valence electrons and increase their stability by gaining electrons to become anions.
Answer: Because they are on the father side of the periodic table
Explanation: Electronegativity increases as you move from left to right on the periodic table
Which element’s symbol could replace the question mark in the diagram?
boron (B)
neon (Ne)
rubidium (Rb)
arsenic (As)
Answer:
D- Arsenic (As)
don’t fail pls :) ✨
The Arsenic (As) element's symbol could replace the question mark in the diagram. Therefore, option D is correct.
What is an electron dot diagram?An electron dot diagram is a diagram used to represent the valence electrons of an atom in a simple way. Valence electrons are the electrons in the outermost shell of an atom, which are involved in chemical bonding.
In an electron dot diagram, the symbol of the element is used to represent the nucleus and inner electrons of the atom, and dots are placed around the symbol to represent the valence electrons. Each dot represents one valence electron, and the dots are placed on each of the four sides of the symbol (top, bottom, left, and right) before doubling up.
Thus, the Arsenic (As) element's symbol could replace the question mark in the diagram. Therefore, option D is correct.
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Your question is incomplete, most probably the full question is this:
Which element’s symbol could replace the question mark in the diagram?
boron (B)
neon (Ne)
rubidium (Rb)
arsenic (As)
What percent of the universe's age is the first 400,000 years?
Answer:
the globuler cluster
Explanation:
hope this helps maybe next time show anwsers
Find the element. Plz help!
Answer:
Hydrogen.
Explanation:
We see in the nucleus that we have 1 proton and 1 neutron.
The number of protons in the nucleus determines which element it is.
Element with 1 proton is the 1st element on the Periodic Table, Hydrogen.
Which substance can be decomposed by chemical means? a. calcium b. argon c. sodium chloride d. aluminum
which can occur in a physical changen?
Find the average atomic mass of smithium ?
Answer:
google friend tell me
Explanation:
You will have to look up the isotopic distribution of lithium nuclei. ALL lithium nuclei have 3 positively charged nuclear particles, protons, i.e. Z = 3 . These 3 particles give rise to the element's identity. If you take the weighted average of ALL lithium nuclei, we get an average mass of 6.941 g⋅mol−1
Why are journal articles important in the spread of scientific knowledge?
Help me pls guy’s
Answer:
When published, each article expands the library of scientific literature available to all scientists and contributes to the overall knowledge base of the discipline of science. They report new research for the first time.
HELP PLEASE
Chemical name for As2S3
Answer:
Chemical name for As2S3 is Arsenic sulfide
Explanation:
Answer:
Arsenic Sulfide
Explanation:
Write a complete, balanced chemical equation where tin metal reacts with aqueous hydrochloric acid to produce tin(II) chloride and hydrogen gas. Include states.
From the equation, which element is oxidized, and which element is reduced?
Answer:
Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)
Explanation:
The net reaction is Z n ( s ) + 2 H + ( a q ) → Z n 2 + ( a q ) + H 2 ( g ) The C l − ions are spectators - they don't change.
Show all work: A metal bar has a length of 5.0 cm, a width of 3.0 cm, and a height of 1.0 cm. What volume of water, measured in deciliters, would this bar displace?
15 cm
and I have to explain but there's nothing to explain so yea
Fill in the blank. An answer would be great right now!!! I’m having trouble with science. thanks!!
Answer:
1. Richter 2. Moment
Hope this helps !!
A compound is always made up of the same ____ in the same proportions.
Answer:
elements
Explanation:
A compound always consists of the same elements in the same ratio. If the same elements combine in different ratios, they form different compounds
what is the significant figures of 12.00
During STATIC ELECTRICITY to what type of objects & direction do electrons ALWAYS move to?
1 point
QUESTION 5: What happens if you reset and place the refrigerator instead
of the wooden box with an applied force fo 200 Newtons for about 3
seconds? *
O The speed of the skateboard increases compared to the wooden box
O The speed of the skateboard decreases compared to the wooden box
Answer: The speed of the skateboard decreases compared to the wooden box
Explanation: well, umm... if you placed a refrigerator on a skateboard... that will be difficult to move, if anything it will brake the board!
A wooden box is much lighter than a refrigerator
Q5 4.70 g of methanoic acid reacts to form 3.60 g of methanoic
anhydride. The equation for this reaction is:
2HCOOH + (CHO),0 + H2O
Calculate the percentage yield of this reaction.
Answer:
The anwser is always Jesus.
Explanation:
Things can only go downhill from here
Predict the charge on the monatomic ions formed from the following atoms in binary ionic compounds:
(a) I
(b) Sr
(c) K
(d) N
(e) S
(f) In
How are covalent molecules named?
A. A number is used in front of each element's name, and the first element is changed to end in -ide.
B. A prefix is added to each element's name, and the second element is changed to end in -ide.
C. A roman numeral is used to indicate the number of atoms of each element.
D. The name of each element is followed by a number to indicate the amount of atoms.
Answer:
A prefix
Explanation:
you're welcome
The covalent molecules named as,
A prefix is added to each element's name, and the second element is changed to end in -ideSo, option B is correct one.
What is covalent molecules?The molecule formed by sharing of electrons between atoms is called covalent molecules .The atoms which form covalent molecules must have similar or less electnegativity difference.Examples of covalent molecules are hydrogen molecule [tex]H_{2}[/tex] ,carbon dioxide, methane etcTo learn more about covalent molecules,
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Which of the following is not a compound? Sulfur, sodium chloride, ammonia, carbon dioxide
Answer:
Carbon monoxide is a colorless, odorless, and tasteless flammable gas that is slightly less dense than air.
Which percentage is in the appropriate range for a snack to be considered a “good source” of nutrients?
15 percent
35 percent
40 percent
50 percent
Answer:
15
Explanation:
Nuclear chemistry findings contradict __________________ theory of indivisible atoms.
Answer:
atomic theory
Explanation:
What did electrons from the ionized air do to the oil drops?
help me please i have it due soon
Answer:
B
Explanation:
I think it is B. That is because when you are falling, your just going to fall faster and faster.
I hope this helps!
Answer:
B
Explanation:
The third force the jumper experiences is a spring force due to the bungee cord. The amount that the bungee cord pulls back on the jumper depends on how far the cord has been stretched, i.e. the farther the jumper has fallen, the more the cord pulls back on him or her.
Julio eats a taco for dinner. What represents a physical change in the taco?
A) saliva changing the starch in the crust to sugar
B) teeth tearing off a bite of a taco
C) chemicals in the stomach digesting proteins
D) breaking down of fats in the taco by bile
The physical change is a modification in the structure of the chemical substance. Teeth tearing off a bite of a taco represents a physical change. Thus, option B is correct.
What is a physical change?A physical change is an alteration in the structure of the chemical involved in the substance. In a physical change, the composition of the chemical remains intact and does not change. It includes changes in texture, temperature, shape, and phase of matter.
The processes like dissolving, boiling, cutting, melting, bending, and freezing are said to be physical changes. The teeth-bitting tacos result in smaller bites is a physical change as there is a change in the shape and size but not the composition.
Therefore, option B. the teeth tearing tacos is an example of physical change.
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When fat comes in contact with sodium hydroxide, it produces soap and glycerin. Determine whether this is a physical change or a chemical change. Explain your answer.
Explanation:
Answer. What comes in contact with Sodium Hydroxide to form soap and glycerine it is a chemical change because you cannot reverse this change and also the products formed are the results of a chemical reaction
Answer:
Its a chemical change because its property is changed.
Explanation: