Answer:
Explanation: Mendeleev arranged the elements on the basis of their atomic mass. Melting and boiling point were used as the physical characteristics in deciding the position of elements. He arranged the elements and wrote the formula of their oxides and hydrides which seemed to possess same chemical formula.
Explanation:
Which element has fewer than 4 dots In its Electron dot diagrams
Answer:Strontium (Sr) and Gallium (Ga)
Explanation:
Strontium (Sr) and Gallium (Ga) are the elements which have fewer than four dots in the electron dot diagrams. Explanation: Electron dot diagrams are the diagrams which represent the valence electrons in an element. The electrons are represented by the dots in these diagrams.
water is denser than oil. When frozen, the oil sinks to the bottom. Why?
Answer: When water freezes it gets larger and becomes a solid but it still weighs the same as when it was a liquid form. When it becomes larger it takes up space but makes it less dense. Ok so getting to the point- oil unlike water becomes more dense when frozen so this is why oil sinks in water. Sorry if this was confusing but I hope it helped have a great day and god bless you :3
d
1.123 L
Question 7 (1 point)
Conversion Factors:
1 tsp = 5 mL
1 quart - 0.946 L
1 cup 48 tsp
1 tbsp = 3 tsp
1 ml. = 7 drops
1 L=1000 ml
1 cup - 110 g
1 kg = 1000 g
1 gallon = 4 quarts
1 cm 1 mL
1 cup - 200 ml
1 m = 1,000,000 cm
How many grams are in 4.78 cups?
са
b
0.043 8
5258 g
114.78 g
4.78 g
oc
od
Answer:
can you provide a picture?
When finding the density of a solid, which situation prevents us from being
able to accurately find the volume displacement?
a) if the solid floats
b) if we use an analytical balance
c) if the solid sinks
d) if we use a graduated cylinder
Answer:
a) if the solid floats
Explanation:
Hello,
In this case, since the determination of the volume of a solid when submerged in water requires to use an analytical balance to measure the mass, but also it is necessary that the solid sinks in order to completely displace the what in the graduated cylinder which accurately provides the volume of the solid via its scale. Therefore, a draw back is a) if the solid floats since the water is not completely displaced.
Best regards.
Theories in science can be disproved through new or extended research.
1. True
2. False
Answer:
True
Explanation:
This is true because technology advances all the time and even Newton's "Laws" could be disproved in the future.
Answer:
True
Explanation:
Based on new research we find out new things
The prefix 'mili-' means a thousandth,
So a mili-liter is a thousandth of a liter.
1 mililiter = 1/1000 liter
How many liters is 1,979 mililiters
Round your answer to the nearest tenth of a liter,
Will GIVE BRAINLY
Compare atoms and molecules.
Answer: An atom is the sub-component of a molecule, or the smallest unit of matter. It is the smallest part an element can divide into. A molecule is made up of atoms that are bound by ionic, covalent or metallic bond.
Answer:
veryy help ful
Explanation:
An atom is the sub-component of a molecule, or the smallest unit of matter. It is the smallest part an element can divide into. A molecule is made up of atoms that are bound by ionic, covalent or metallic bond.
100 POINTS!! PLEASE HELP WILL MARK BRAINLIEST
Answer:
a. 13.5 mL
b. 4.01 g and 112.0 mL
c. 22.3 mL
d. 2.62 g/mL
e. it will float on bromine and mercury
Explanation:
a. 13.534=10/x
b. 8.920=x/0.45 and 8.920= 1000/x. the reason its 1000 is because 1 kg is converted to grams, same unit for the density.
c. 0.789=17.6/x
d. 68.2-56.3 is the volume of the quartz. so 31.18/11.9 is the density
e. 33.93/12.5 gives you the density which is 2.7144. so in order to float, it has to be in a substance with a greater density such as bromine with a 3.119 density.
Hope that helped!
IF YOU ANSWER FIRST, I'll give you the crown hehe
Data can be collected by observations and performing experiments.
True OR False
Answer:
True
Explanation:
Using the tools and knowledge of science to solve a problem or build new technology is called...
Answer:
Invention
Explanation:
Scientific ideas can be applied in novel was to solve new scientific problems and create new technology. This process helps to make life easier and better.
The application of scientific knowledge to solve new problems and create new technology is generally referred to as invention.
Which statement accurately describes the Doppler effect?
Answer:
Explanation:
These statements accurately describe the Doppler Effect: It indicates galaxy motion through light wavelengths. It indicates a galaxy moving toward Earth through red shift. I hope this helps.
Which of the following describes radioactive decay by beta particle emission?a. The daughter isotope has an atomic number two less than the parent and a mass number four less.b. The mass number of the daughter isotope is one more than the parent, and both isotopes have the same atomic number.c. The atomic number of the daughter isotope is one more than the parent; the mass numbers are the same.d. The daughter isotope has an atomic number one less than the parent and a mass number two less.
Answer:
c. The atomic number of the daughter isotope is one more than the parent; the mass numbers are the same
Explanation:
Radioactive decay by beta particle emission involves the emission of an electron.
An electron is a very light particle and its emission does not reflect a loss in mass of the parent molecule. However, the atomic number of the parent molecule increase by one due to the retention of a proton.
Therefore, the daughter isotope has the same mass number as the parent molecule but its atomic number increases by one unit.
An example of beta particle emission is given below;
Th₀(234) ---> Pa₉₁(234) + e₋₁(0)
Thorium₉₀(234) emits a beta particle, e₋₁(0) to give Protactinium₉₁(234)
Answer:
c
Explanation:
When of a certain molecular compound X are dissolved in of dibenzyl ether , the freezing point of the solution is measured to be . Calculate the molar mass of X. If you need any additional information on dibenzyl ether, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to significant digit.
This question is incomplete, the complete question is;
When 4.28 g of a certain molecular compound X are dissolved in 60.0 g of dibenzyl ether [(C₆H₅CH₂)₂0] , the freezing point of the solution is measured to be -3.2°C . Calculate the molar mass of X.
If you need any additional information on dibenzyl ether, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to significant digit.
Answer: molar mass of solute (X) is 88.03 g/mol
Explanation:
Given that;
mass of solute = 4.28 g
mass of solvent = 60.0 g = 0.060 kg (Dibenzyl ether)
depression constant kf = 6.17 °CKg/mol
Freezing Point of solvent T₀ = 1.80°C (Dibenzyl ether)
freezing point of solution Tsol = -3.20°C
Now we know that
Depression in freezing point ΔTf = depression constant kf × molaity m
and (ΔTf = T₀-Tsol)
so T₀ - Tsol = kf × m
we substitute
1.80 - (-3.20) = 6.17 × m
5 = 6.17 × m
m = 5 / 6.17
m = 0.8103 kg/mol
so molaity m = 0.8103 kg/mol
we know that
Molaity of solute m = (mass of solute / M.wt of solute) × ( 1 / mass of solvent in Kg)
solve for molar mass of solute
molar mass of solute = (mass of solute / molaity) × ( 1 / mass of solvent in Kg)
now we substitute
molar mass = (4.28g / 0.8103 kg/mol) × (1 / 0.060kg)
molar mass = ( 5.2839 × 16.66 ) g/mol
molar mass = 88.0297 g/mol ≈ 88.03 g/mol
Therefore molar mass of solute (X) is 88.03 g/mol
The periodic table of elements is organized by the number of
Answer:
the increasing mass number
Solve each of the following problems using one or more conver-sion factors:a. A container holds 0.500 qt of liquid. How many milliliters of lemonade will it hold?b. What is the mass, in kilograms, of a person who weighs 175lb?c. An athlete has 15% body fat by mass. What is the weight of fat, in pounds, of a 74-kg athlete?d. A plant fertilizer contains 15% nitrogen (N) by mass. In a container of soluble plant food, there are 10.0 oz of fertilizer. How many grams of nitrogen are in the container?
Answer:
a. 473mL.
b. 79.38kg
c. 24.47lb of fat
d. 42.5g of N.
Explanation:
a. A qt is equal to 946mL. 0.500qt are:
0.500qt * (946mL / 1qt) = 473mL
b. 1lb is equal to 0.4536kg, 175lb are:
175lb *(0.4536kg / 1lb) = 79.38kg
c. The fat in kg of the athlete is:
74kg * 15% = 11.1kg of fat. In pounds:
11.1kg * (1lb / 0.4536kg) = 24.47lb of fat
d. The mass of nitrogen in the fertilizer is:
10.0oz * 15% = 1.5oz of N
1 oz is equal to 28.35g. 1.5oz are:
1.5oz * (28.35g / 1oz) = 42.5g of N
Which expression correctly describes energy using SI units? A. 1 J=1kg•m^2/s^2 B. 1 J= 1kg•m/s^2 C. 1 J= 1kg• m/s D. 1 J= 1kg•m^2/s
Answer:
A. 1 J=1kg•m^2/s^2
Explanation:
Energy refers to the capacity to do work. According to the International System of units (SI units), energy is measured in Joules.
Energy is represented by the force applied over a distance. Force is measured in Newton (N) and distance in metres (m). Hence, energy is Newton × metre (N.m)
Newton is derived from the SI units of mass (Kilograms), and acceleration (metres per seconds^2) i.e Kg.m/s^2, since Force = mass × acceleration.
Since; Energy = Newton × metres
If Newton = Kg.m/s^2 and metres = m
Energy (J) will therefore be; Kg.m/s^2 × m
1J = Kg.m^2/s^2
A reaction in which A, B, and C react to form products is zero order in A, one-half order in B, and second order in C.
a. Write a rate Jaw for the reaction.
b. What is the overall order of the reaction?
c. By what factor does the reaction rate change if [A] is doubled (and the other reactant concentrations are held constant )?
d. By what factor does the reaction rate change if [B] is doub led (and the other reactant co ncen trati ons are held consta nt )?
e. By what factor does the reaction rate change if [C] is doubled (and the other reactant concen trations are held constant)?
f. By what factor does the reaction rate change if the concentrations of all three reactants are doubled?
Answer:
a. [tex]r=k[B]^{1/2}[C]^2[/tex]
b. [tex]Order=3.5[/tex]
c. It does not affect the rate.
d. [tex]\sqrt{2}[/tex].
e. 4.
f. 4[tex]\sqrt{2}[/tex].
Explanation:
Hello,
In this case, considering the given information, we have:
a. [tex]r=k[B]^{1/2}[C]^2[/tex]
b. By adding 1/2 and 2 (powers for B and C), the overall order is:
[tex]Order=\frac{1}{2} +2\\\\Order=3.5[/tex]
c. It is not changed, since the concentration of A is not affecting the rate due to its specific zeroth-order.
d. In this case, if the concentration of B is doubled, such term in the equation shows:
[tex]\sqrt[n]{x} \frac{r_f}{r_i}=\frac{[2B]^{(1/2)} [C]^2}{[B]^{(1/2)}[C]^2} \\\\\frac{r_f}{r_i}=\frac{[2B]^{(1/2)}}{[B]^{(1/2)}}\\\\\frac{r_f}{r_i}=(\frac{2}{1})^{1/2}\\\\r_f=\sqrt{2} r_i[/tex]
It means that the rate increases by a factor of [tex]\sqrt{2}[/tex].
e. In this case, if the concentration of C is doubled, such term in the equation shows:
[tex]\frac{r_f}{r_i}=\frac{[B]^{(1/2)}[2C]^2}{[B]^{(1/2)}[C]^2} \\\\\frac{r_f}{r_i}=(\frac{[2C]}{[C]})^{2}\\\\\frac{r_f}{r_i}=(\frac{2}{1})^{2}\\\\r_f=4r_i[/tex]
It means that the rate increases by a factor of 4.
f. In this case, if the concentration of both B and C are doubled, such terms in the equation shows:
[tex]\frac{r_f}{r_i}=\frac{[2B]^{(1/2)}[2C]^2}{[B]^{(1/2)}[C]^2} \\\\\frac{r_f}{r_i}=\frac{2^{(1/2)}2^2}{1^{(1/2)}1^2} \\\\\frac{r_f}{r_i}=4\sqrt{2} \\\\r_f=4\sqrt{2} r_i[/tex]
It means that the rate increases by a factor of 4[tex]\sqrt{2}[/tex].
Best regards.
An air bubble at the bottom of lake with temperature 7 0C and pressure of 3.2 atm has a radius of 2.5 cm. It rises to the surface where the temperature is 25 oC and atmospheric pressure is 1 atm. What is the volume of the bubble at the surface? Assume perfect gases. V=(4/3)πr3.
Answer:
[tex]2.0 \times 10^{2} cm^{3}[/tex]
Explanation:
Step 1: Given data
Initial pressure (P₁): 3.2 atmInitial temperature (T₁): 7 °C = 305 KInitial radius (r₁): 2.5 cmFinal pressure (P₂): 1 atmFinal temperature (T₂): 25 °C = 298 KFinal volume (V₂): ?Step 2: Calculate the initial volume
We will use the following expression.
V = 4/3 × π × r³
V = 4/3 × π × (2.5 cm)³
V = 65 cm³
Step 3: Calculate the final volume
Assuming ideal behavior, we can calculate the final volume of the bubble using the combined gas law.
[tex]\frac{P_1 \times V_1 }{T_1} = \frac{P_2 \times V_2 }{T_2}\\V_2 = \frac{P_1 \times V_1 \times T_2 }{T_1 \times P_2} = \frac{3.2atm \times 65cm^{3} \times 298K }{305K \times 1atm} = 2.0 \times 10^{2} cm^{3}[/tex]
2.
Question: How much water is best for a pea plant to grow?
Answer:
Explanation:
Growing Peas
Planting depth should be roughly 2 inches with a spacing of about 2 inches apart. Water well at planting and provide at least 1 inch of water per week, particularly during the flowering and pod production stages. As the temperature rises, the vines may need to be deeply watered almost every day.
Make sure to moniter it and change the water depending on how dry or overwatered it looks like. :)
What is the difference between solid, liquid and ice? Use ice, water and steam as examples.
Answer: A solid is something that can hold its own shape and is hard to compress (squash). However, ice is different from most solids because its molecules are less densely packed than in liquid water so ice takes up a little more space than the same amount of liquid water. This is why ice floats.
Explanation: Hope it works!!!!!
Based on Chromium's position on the periodic table, which statement describes the element
chromium (Cr), atomic number 24?
A. chromium is a nonmetal and therefore a good conductor of heat and electricity
B. chromium is a metal that is more reactive than potassium
C. chromium is a metal that is less reactive than sodium
D. chromium is a noble gas that is not reactive
Answer:
C. chromium is a metal that is less reactive than sodium.
Explanation:
Hello.
In this case, since chromium is in period 4 group VIB we infer it is a transition metal which slightly reacts with acids and poorly reacts with oxygen and other oxidizing substances. Thus, in comparison with both sodium and potassium which are highly reactive even with water as they get on fire, we can say that it is less reactive than both potassium and sodium, therefore, answer is: C. chromium is a metal that is less reactive than sodium.
Best regards.
A gold-colored pebble is found in a stream. Its mass is 23.2 mg and its volume is 1.20 mm3. What is its density in grams per cubic centimeter? Is it gold?
Answer:
The density in g/cm3 is 1.9333(put a line above the 3's to show it's repeating).
And no it is not gold because the density of gold in g/cm3 is 19.3.
Explanation:
Divide the mass by the volume in order to get an object's Density.
so, 23.2 divided by 1.20 mm3
=1.93333333 g/cm3
That is the density then you find out the density of gold in grams per cubic centimeter, that is 19.3 g/cm3
For example, gold will always have a density of 19.3 g/cm3; if a mineral has a density other than that, it isn't gold.
An atom or ion has 41 neutrons, 36 protons, and 36 electrons. Identify the element symbol, and determine the mass number
and charge for this atom or ion.
Answer:
Element symbol: Kr.
Mass number: 77.
Charge : 0.
Explanation:
Hello,
In this case, since such substance has the same amount of protons and electrons we can infer it is an atom whose number of neutrons is defined by considering its atomic mass or mass number and atomic number which is actually equal to the number of protons and electrons (36):
[tex]neutrons=atomic\ mass - atomic\ number[/tex]
In such a way, solving for the atomic mass we obtain:
[tex]atomic\ mass=neutrons+ atomic\ number\\\\atomic\ mass=41+36=77[/tex]
It means that the element is krypton (Kr) as it has 36 electrons and protons so its charge is 0.
Best regards.
17. Elements in the periodic table are arranged according to their.
(2 x 109) x (5 x 105).
Answer:
114450
Explanation:
2*109 = 218
5*105 = 525
218*525 = 114450
How many moles is 90.93 grams of aluminum?
A)2453.47 moles
B)6.02x1023 moles
C)3.37 moles
D)2.107x1024 moles
Answer:
C) 3.37 moles .
Explanation:
Hello,
In this case, considering that the atomic mass of aluminum is 27.0 g/mol, the moles in 90.93 g of aluminum are computed via the following dimensional analysis:
[tex]n=90.93 gAl*\frac{1molAl}{27.0gAl} \\\\n=3.37molAl[/tex]
Thus, answer is C) 3.37 moles .
Best regards.
The basic principle in balancing a chemical equation is to ______. View Available Hint(s) The basic principle in balancing a chemical equation is to ______. have the sum of coefficients in reactants equal to that in the products have the same number of atoms of each element in the reactants and in the products have the same number of reactants as products have the same number of molecules of each substance in the reactants and in the products
Answer:
have the same number of atoms of each element in the reactants and in the products
Explanation:
The basic principle in balancing a chemical equation would simply be to have the same number of atoms of each element in the reactants and in the products.
A balanced chemical equation is one that has the same number of atoms of each element on the reactant and the product's side of the equation. For example, consider the equation below:
[tex]H_2 + O_2 --> H_2O[/tex]
On the reactant's side, there are 2 atoms of H and O while there are 2 atoms of H and 1 atom of O on the product's side. This is an imbalanced equation. In order for it to be balanced, the number of atoms of H and O on the reactant side must be equal to the number of H and O on the product side as below.
[tex]2H_2 + O_2 --> 2H_2O[/tex]
I need help with this please
Answer:
Not sure ask Estellia
Explanation:
Answer:
h= 4.9
Explanation:
l x w x h = a
7.66 x 3.75 x h = 141
28.725h = 141
Divide both sides by 28.725 to solve for h.
Select the descriptor (A, B, C, D): that best describes the relationship between the reactants and products below: Reactant ProductCH3CH3OH + H2O A B C D CH3CH2O^- + H3O^+
Answer:
A- conjugate acid
B- conjugate base
C- conjugate base
D- conjugate acid
Explanation:
According to the Brownstead-Lowry definition of acids, an acid donates a proton while a base accepts the proton.
If we look at the species ABCD, species A and D donate protons while species B and C accept protons.
C is the conjugate base of A while D is the conjugate acid of B, hence the answer.
Hafnium (Hf) has six naturally occurring isotopes: 0.16% of 174Hf, with an atomic weight of 173.940 amu; 5.26% of 176Hf, with an atomic weight of 175.941 amu; 18.60% of 177Hf, with an atomic weight of 176.943 amu; 27.28% of 178Hf, with an atomic weight of 177.944 amu; 13.62% of 179Hf, with an atomic weight of 178.946 amu; and 35.08% of 180Hf, with an atomic weight of 179.947 amu. Calculate the average atomic weight of Hf.
Answer:
178.463 amu
Explanation:
Average atomic weight of Hafnium is calculated as follows;
[(0.0016 × 173.940) + (0.0526 × 175.941) + (0.186 × 176.943) + (0.2728 × 177.944) + (0.1362 × 178.946) + (0.3508 × 179.947)] =0.278 + 9.234 + 32.911 + 48.543 + 24.372 + 63.125 = 178.463 amu
Therefore, average atomic weight of Hafnium is 178.463 amu
