Answer:
Between oxygen and selenium, oxygen is more electronegative because of more ionisation energy and small size
Explanation:
?
The group number tells the number of
Elements in the column
Number of valence electrons
O Number of energy levels
O Number of protons in the elements
Answer:
number of valence electrons
Explanation:
elements in the same group has same number of valence electrons
Calculate the number of moles of neon gas in 8.15 x 10^24 atoms of neon gas.
1.35 moles Ne
0.135 moles Ne
135 moles Ne
13.5 moles Ne
Answer:
13.5 moles of Ne
Explanation:
1 mole of any gas contains 6.02 x 10²³ atoms of gas
6.02 x 10²³ atoms of neon is equal to 1 mole of neon .
8.15 x 10²⁴ atoms of neon is equal to 1 x 8.15 x 10²⁴ / 6.02 x 10²³ moles
= 8.15 x 10²⁴ / 6.02 x 10²³ mole o neon
= 13.5 moles of Ne .
Which of the following is considered a sign of a chemical change?
Which of the following elements has the largest electronegativity? A) Bismuth B) Nitrogen C) Potassium D) Arsenic
Which types of reactions would result in the formation of precipitate?
Answer:
Double Displacement Reaction
Explanation:
A double displacement reaction is a type of chemical reaction in which the reactant ions exchange places to form new products. Usually, a double displacement reaction results in precipitate formation.
A 0.2027 gram sample of finely powdered limestone (mainly CaCO₃) was dissolved in 50 mL of 0.1035 M HCl. The solution was heated to expel CO₂ produced by the reaction. The remaining HCl was then titrated with 0.1018M of NaOH and it required 16.62 mL. Calculate the percentage of CaCO₃ in the limestone sample? CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
Answer:
Explanation:
CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
100 gm + 2000 mL of M HCl
Amount of HCl remaining = .1018 M of 16.62 mL
= .1018 x 16.62 mL of M HCl
= 1.69 mL of M HCl
Initial HCl taken = 50 mL of .1035 M HCl
= 5.175 mL of M HCl
HCl reacted = 5.175 - 1.69 mL of M HCl
= 3.485 mL of M HCl
2000 mL of M HCl reacts with 100 gm of CaCO₃
3.485 mL of M HCl will react with .174 grams of CaCO₃
percentage of calcium carbonate = .174 x 100 / .2027
= 85.84 %
What type of heat transfer happens in the Inner Core?
Answer: Conduction
Explanation:
What physical property of the metal rods was being tested during step 4 of the procudure?
4. Measure and record how long it takes heat from the hot plate set on "high" to melt the wax ball.
A.
magnetism
B.
thermal conductivity
C.
electrical conductivity
D.
density
Answer:
B. thermal conductivity
Explanation:
They physical property being tested during the fourth step is the thermal conductivity of the materials.
Thermal conductivity is the ability of a body to transmit heat energy from one place to another.
Since we are measuring how long it takes for heat from the hot plate to reach the wax ball, this is a typical experiment for measuring thermal conductivity. Most metals are good conductors and heat energy moves fast in them.Non-metals are poor conductors with low thermal conductivity.The ___ has many functions; one is to regulate growth.
Growth hormon somatotropin
Can an Atom be broken down into a smaller substance? Yes or No Explain.
Answer:
Yes
Explanation:
A atom is made out of 3 elements, protons which are positive charges, electrons which are negative charges that swirl around the atom, and a neutron with a neutral charge. The nucleus of the atom is basically the center of the atom.
#7- pls help me ill mark you brainliest and ill give you 5 stars <3
Answer:
I think it is synthesis
Answer:
The answer is Synthesis
Explanation:
The two objects combine to make a bigger object
#8- please help i suck at this, ill mark brainliest
Answer:
A. Synthesis
B. Combustion
C. Single-replacement
D. Decomposition
Explanation:
A: Synthesis. Two reactants are combined to form, or synthesize, one product.
B: Combustion. This is the general reaction for combustion. When something combusts, oxygen must be present. Carbon dioxide and water must also be produced.
C: Single-replacement. The oxygen from Fe₂O₃ is moved to K to form K₂O. Only one thing is being moved, or replaced.
D: Decomposition. You have one compound that breaks into, or decomposes, into two products.
Joe bought a roll of gray duct tape containing 5400 inches. If there are 5280 feet in a mile, how
many miles long is Joe's roll of duct tape?
Answer:
STANDARD: 0.085 mi, 450 ft, or 150 yds
METRIC: 0.137 km, 137.16 m, or 13716 cm
Explanation:
4. Advection fog forms when warm moist air comes in from the Pacific Ocean and
blows over the cold California current.
A.True
B.False
Answer:
A, True
Explanation:
Explain why the mass number of oxygen is 16
Answer:
Oxygen has an atomic number of 8 , and the mass number of an atom is the sum of its atomic number plus its neutron number. We got the mass as 16 units, and so it'll have 16−8=8 neutrons.
Explanation:
Plz help! The best answer will be marked as brainliest!
Make a funny sentence for the beneficial or great uses of magnesium
I DON¨T WANT A MEME!
Here is an example for Mercury, it HAS to for Magnesium
¨I have a long history of use in fluorescent lighting so I can light up any room ¨
Answer:
"Like when people say like im a party fowl but I'm like OMg, I'm like the reason everyone loves the 4th of July like I am 4th of July.
Explanation:
As magnesium ignites easily in air and burns with a bright light, it's used in flares, fireworks and sparklers. I imagine Magnesium talks like a valley girl lol.
Diffusion of Ammonia in an Aqueous Solution. An ammonia (A)-water (B) solution at 278 K and 4.0 mm thick is in contact at one surface with an organic liquid at this interface. The concentration of ammonia in the organic phase is held constant and is such that the equilibrium concentration of ammonia in the water at this surface is 2.0 wt 'Yo ammonia (density of aqueous solution is 991.7 kg/m3) and the concentration of ammonia in water at the other end of the film 4.0 mm away is 10 wt % (density of 961.7 kg/m3). Water and the organic are insoluble in each other. The diffusion coefficient ofNH3 in water is 1.24 x 10- 9 m 2/sCalculate the flux N_B. Explain.
Answer:
The Flux N_B = 0
Explanation:
So, we are given the following set of data or parameters which is going to help in solving this particular Question. So, let us take each at a time;
=> "An ammonia (A)-water (B) solution at 278 K and 4.0 mm thick is in contact at one surface with an organic liquid at this interface."
=>" 2.0 wt 'Yo ammonia (density of aqueous solution is 991.7 kg/m3) and the concentration of ammonia in water at the other end of the film 4.0 mm away is 10 wt % (density of 961.7 kg/m3). ''
With the information above, we can determine the N_A(which the question did not specify that we should calculate).
For the value of N_B, it will be equals to zero(0) because the insolubility of water in organic solvent.
Classify the following reactions and complete the given below
A) NaCl + AgNO3 - NaNO3 + AgCl
Answer:
chemical equation balance.
Explanation:
if you need more explanation , comment.
What happens to the atomic radius when an electron is lost?
A. The positive ionic radius is the same size as the neutral atomic
radius.
B. The positive ionic radius does not follow a trend with the neutral
radius.
C. The positive ionic radius is smaller than the neutral atomic radius.
D. The positive ionic radius is larger than the neutral atomic radius.
Answer:the positive ionic radius is smaller than the neutral atomic radius
Explanation:
Answer:The positive ionic radius is smaller than the neutral atomic radius.
Explanation: just took the test
Explain why the several different types of microscopes are all necessary.
Answer:
some zoom in farther
Explanation:
some microscopes zoom in farther than others so we can see even smaller things
Answer question number 3
What will the coefficients be for the following balanced equation? (a) N2 + (b) H2 → (c) NH3
Answer:
his reaction is the synthesis of Ammonia using Nitrogen and Hydrogen gas.
N
+
H
→
N
H
3
We must remember that Nitrogen and Hydrogen are both diatomic molecules in their standard gas form. This adjusts the equation to
N
2
+
H
2
→
N
H
3
Now we need to adjust coefficients in order to balance the atoms on each side of the equation. Currently we have 2 atoms of nitrogen and 2 atoms of hydrogen on the reactant side and 1 atom of nitrogen and 3 atoms of hydrogen on the product side.
We can balance the hydrogens by placing a coefficient of 2 in front of ammonia and a coefficient of 3 in front of the hydrogen.
N
2
+
3
H
2
→
2
N
H
3
This gives us 6 hydrogen on each side and coincidentally the nitrogens now equal 2 on each side.
I hope this was helpful.
Explanation:
Answer:
1N2 + 3H2 →2NH3
Explanation:
Plato answer
How many d electrons does I (atomic number
53) possess?
1. 10
2. 5
3. 8
4. 0
5. 20
6. 53
7. 16
Answer:
6. 53 is the answer. Hope this helps:)
The number of d electrons that an atom of atomic number 53 possess are 20. Thus, the correct option for this question is 5.
What is an Atomic number?An atomic number may be defined as the number of protons in the nucleus of an atom that significantly represents the characteristic of a chemical element and determines its specific place in the modern periodic table.
According to the modern periodic table, an element that has an atomic number of 53 is known as Iodine. Its electronic configuration is [tex]1s^2, 2s^2, 2p^6, 3s^2, 3p^6, 4s^2, 3d^1^0, 4p^6, 5s^2, 4d^1^0, 5p^5[/tex]. Thus, according to this electronic configuration, the total number of d electrons are [tex]3d^1^0 and 4d^1^0[/tex].
Therefore, the number of d electrons that an atom of atomic number 53 possess are 20. Thus, the correct option for this question is 5.
To learn more about Electronic configuration, refer to the link:
https://brainly.com/question/26084288
#SPJ2
Assume that the pendulum clock shown in the photograph is a closed
system
Which statement describes evidence that the pendulum's energy is conserved
even as it eventually stops moving?
A. Energy must be added to the pendulum to keep it from slowing
down
B. Some of the clock's matter is transformed into new energy
C. The amount of each type of energy in the system can be
measured
D. All its mechanical energy is transformed into other forms of
energy
Answer:
Explanation:
d
Answer:
D. All it’s mechanical energy is transformed into other forms of energy.
Explanation:
I got it right
How many moles of gold, a U, are in 3.60×10^-5 G of gold?
Answer:
See Below.
Explanation:
This is a conversion problem:
Using the molar mass of Gold (given in a periodic table) which is 196.97g/mol
you have
[tex](3.60*10^-5 g) *\frac{1moles}{196.97g}[/tex]
you always arrange the equation in a way to cancel whatever you don't want (grams) and leave what you do want (moles). Here grams cancel (top and bottom), so you're left with:
[tex]\frac{(3.60*10^-5 g) *(1)}{196.97} = 1.83*10^-7[/tex] moles of Gold
a cylindrical object has a diameter of 1.25 cm and a height of 6.48 cm. what is its volume?
The volume of cylinder = 7.948 cm³
Further explanation
Volume is a derivative quantity derived from the length of the principal
The unit of volume can be expressed in liters or milliliters or cubic meters
The volume of the aquarium is almost the same as the beam namely:
V = length x width x height
The volume of a cylinder can be formulated :
[tex]\tt V=\pi.r^2.h[/tex]
r = radius
h = height
radiusDiameter of cylinder = 1.25 cm
radius=r :
[tex]\tt \dfrac{1.25}{2}=0.625~cm[/tex]
volume[tex]\tt V=\pi\times 0.625^2\times 6.48\\\\V=\boxed{\bold{7.948~cm^3}}[/tex]
How many moles are in 5.25 X 10 25
atoms of Au?
Answer:
The answer is 87.21 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{5.25 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 87.2093023...[/tex]
We have the final answer as
87.21 molesHope this helps you
PLZ HELP ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
Reactivity
Explanation:
Luster. Ductile, and Malleabillity are all physical.
Order the masses from smallest to largest
Can someone please tell me if this right.
Answer:
1. 7.86 × 10⁴ g
2. 7.86 × 10⁴ kg
3. 1.989 × 10¹³ mg
4. 1.989 × 10²⁸ kg
5. 1.989 × 10³³ g
Explanation:
The easiest way to make sure you have the right answer is to convert all units to the same unit.
A. 1.989 × 10¹³ mg = 1.989 × 10¹⁰ g
B. 7.86 × 10⁴ g
C. 1.989 × 10³³ g
D. 7.86 × 10⁴ kg = 7.86 × 10⁷ g
E. 1.989 × 10²⁸ kg = 1.989 × 10³¹
The correct order is B < D < A < E < C
A sample of N2H4 has a mass of 25g. Identify the numerical quantity that is needed to convert the number of grams of N2H4 to the number of moles of N2H4. (You do not need to do the actual calculation.)
Answer:
Molecular Mass
Explanation:
It's asking for the numerical quantity. That quantity would be the Molecular Mass. Take the sample mass and divide it by the molecular mass to get the number of moles.
(14g N * 2) + (1g H *4) = 32g / mol of N2H4
To get # of moles, divide the sample mass by the molecular mass
25g / 32g = 0.78125 moles