Which statement best describes the density of an atom's nucleus?
A The nucleus occupies most of the atom's volume but contains little of its mass,
The nucleus occupies very little of the ston's volume and contains little of its mass.
The nucleus occupies most of the stom's volume and contains most of its mass
The nucleus occupies very little of the ston's volume but contains most of its mass

Answer:

A

Explanation:

In simple terms: Hammer goes one way, air goes the other way.

Answer:

d

Explanation:

i took the test

Answer:

Pb₂O₄

Explanation:

The given species are:

        Pb⁴⁺               O²⁻  

Now, to solve this problem, we use the combining powers which corresponds to the number of electrons usually lost or gained or shared by atoms during the course of a chemical combination.

                                          Pb⁴⁺               O²⁻  

Combining power               4                    2

Exchange of valencies        2                    4

Now the molecular formula is  Pb₂O₄

Answer:

D. the amount of oxygen collected over a period of 12 hours

Explanation:

Photosynthesis is a metabolic reaction performed by the cells of plant. In this reaction, light is used as an energy source to combine carbon dioxide (CO2) and water (H2O) to produce glucose and oxygen gas (O2) as products. In every chemical reaction including photosynthesis, an increase in concentration of reactants will increase the rate of the reaction, which is evident in the amount of products formed.

According to this question where a student is performing an investigation to determine the relationship between a higher than normal concentration of carbon dioxide gas and the rate of photosynthesis. After increasing the concentration of carbon dioxide in water, the student illuminated the plant with a light and collected the bubbles of oxygen gas that were given off from the cut end of the submerged plant.

Based on the above explanation, the best indicator of the rate of photosynthesis in this investigation will be THE AMOUNT OF OXYGEN COLLECTED OVER A PERIOD OF 12 HOURS.

Answer:

Theoretically not directly describing, .Atoms vs Ions an ion is an electrically charged particle produced by either removing electrons from a neutral atom to give a positive ion or adding electrons to a neutral atom to give a negative ion. When an ion is formed, the number of protons does not change.

Neutral atoms can be turned into positively charged ions by removing one or more electrons. A neutral sodium atom, for example, contains 11 protons and 11 electrons. By removing an electron from this atom we get a positively charged Na+ ion that has a net charge of +1.

Atoms that gain extra electrons become negatively charged. A neutral chlorine atom, for example, contains 17 protons and 17 electrons. By adding one more electron we get a negatively charged Cl- ion with a net charge of -1.

The gain or loss of electrons by an atom to form negative or positive ions has an enormous impact on the chemical and physical properties of the atom. Sodium metal, for example, which consists of neutral sodium atoms, bursts into flame when it comes in contact with water. Neutral chlorine atoms instantly combine to form Cl2 molecules, which are so reactive that entire communities are evacuated when trains carrying chlorine gas derail. Positively charged Na+ and negatively charged Cl- ions are so unreactive that we can safely take them into our bodies whenever we salt our food.

Explanation:

mark brainlist

Answer:

Each time an excited helium atom falls back from an excited state to its ground state or to a lower energy state, it emits a photon of radiation that shows up as this specific line-emission spectrum.

Explanation:

Answer:

λ  =  1.5 m

Explanation:

Given data:

Speed of wave = 1500 m/s

Frequency of sound = 1000 Hz

Wavelength of sound = ?

Solution:

Speed of wave = frequency × wavelength

by putting values,

1500 m/s  = 1000 Hz ×  λ

λ  =  1500 m/s  / 1000 s⁻¹     (Hz =  s⁻¹ )

λ  =  1.5 m

Answer: 1.5

Explanation:

Well first you do

1500/ 1000= 1.5 which mean

The wavelength is 1.5

Answer:

PRACTICE MULTIPLE CHOICE QUESTIONS FROM UNIT 10

1.) A cylinder is filled with 2.00 moles of nitrogen, 3.00 moles of argon, and 5.00 moles of helium. If

the gas mixture is at STP, what is the partial pressure of the argon?

(A) 152 torr (B) 228 torr (C) 380. torr (D) 760. torr

2.) Compared to the average kinetic energy of 1 mole of water at 0 oC, the average kinetic energy

of 1 mole of water at 298 K is

(A) the same, and the number of molecules is the same

(B) the same, but the number of molecules is greater

(C) greater, and the number of molecules is greater

(D) greater, but the number of molecules is the same

3.) If the pressure on a given mass of gas in a closed system is increased and the temperature

remains constant, the volume of the gas will

(A) decrease (B) increase (C) remain the same

4.) Which gas has approximately the same density as C2H6 at STP?

(A) NO (B) NH3 (C) H2S (D) SO2

5.) At a temperature of 273 K, a 400. milliliter gas sample has a pressure of 760. millimeters of

mercury. If the pressure is changed to 380. millimeters of mercury, at which temperature will

this gas sample have a volume of 551 milliliters?

(A) 100 K (B) 188 K (C) 273 K (D) 546 K

Get the answers to these questions

Back to the Unit 10 Old Tests Pag

Answer:

27.3% of Carbon (C), 72.7% of Oxygen (O).

Answer:

b

Explanation:

Answer:

1280L

Explanation:

Given parameters:

Initial pressure  = 0.727atm

Temperature  = 26.9°C

Initial volume  = 726mL  = 0.726L

New pressure  = 0.412atm

Unknown:

New volume of the gas sample  = ?

Solution:

To solve this problem, we apply boyles law;

            P1V1  = P2V2

P and V are pressure and temperature

1 and 2 are initial and new state

             0.727 x 0.726  = 0.412 x V2

                   V2  = 1.28mL  = 1280L

Answer: i think it is 144.16

Explanation:

Answer:

f = 0.94 ×10²⁴  Hz

Explanation:

Given data:

Frequency of light = ?

Wavelength of light = 3.2 ×10⁻¹⁶ m

Solution:

Formula:

Speed of light = wavelength × frequency

c = λ × f

c = speed of wave = 3×10⁸ m/s

by putting values,

3×10⁸ m/s  = f × 3.2 ×10⁻¹⁶ m

f  =  3×10⁸ m/s   / 3.2 ×10⁻¹⁶ m

f  = 0.94 ×10²⁴ s⁻¹

f = 0.94 ×10²⁴  Hz (Hz = s⁻¹)

1.43 × 10⁻²⁰ mol Li

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Step 1: Define

8.63 × 10³ atoms Li

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

1.43355 × 10⁻²⁰ mol Li ≈ 1.43 × 10⁻²⁰ mol Li

Answer:

There are three forces acting on the skateboard. One of these forces is the weight of the rider. Another is the force of gravity on the board itself. The third is the force of the ground pushing up on the skateboard.

Answer:

a

Explanation:

Answer:

D

Explanation:

Answer:

B

Explanation:

scientists always look for evidence

Answer:

Yea its B

Explanation: The person above me legit toke the answer out of my mouth

Answer:

2.No. because in an open system, gas will blow up & so, if it's measured, it won't have the equal amount of the reactant. But, if you arrange this reaction in a closed system, then it will be the same.

3.2SiO2+4Cl2= 2SiCl4+O2

Explanation:

Answer:

784.4kg

Explanation:

Given parameters:

Mass of Mg  = 200kg

Unknown:

Mass of MgCl₂  = ?

Solution:

  The reaction equation is given as:

            Mg  +  Cl₂ →   MgCl₂

Find the number of moles of the given specie;

  Number of moles of Mg = [tex]\frac{mass}{molar mass}[/tex]   = [tex]\frac{200000}{24.3}[/tex]   = 8230.5mole

So;

   1 mole of Mg will produce 1 mole of MgCl₂

   8230.5mole of Mg will produce 8230.5mole of MgCl₂

Mass of MgCl₂   = number of moles x molar mass

                    Molar mass of MgCl₂  = 24.3 + 2(35.5) = 95.3g/mol

 Mass of MgCl₂   = 8230.5mole x  95.3g/mol  = 784.4kg

Answer:B & C

tell me if im wrong

Answer:

Q 3 c it will reduce rate of photosynthesis in plants that live in the bottom of the lake

Q4 d the atom are in same group

This is right answer because these two elements are Lithium and neon Lithium is present in first group and Neon in last or group 18

Explanation:

Answer:

A is 2, B is 8, and C is 18

Explanation:

I did the Gizmos

The two, eight, and eighteen electrons can be filled in the first, second, and third energy levels respectively.

The electrons revolve in different orbits are known as energy levels or stationary states. These energy levels are numbered as n = 1, 2, 3…… These values are also known as the principal quantum numbers.

The first energy level is also known as 'K' shell or level. The second energy level is called 'L' shell, the third energy level is 'M' shell, and so on.

The electrons present in the K shell contain the least energy whereas the levels contain more energy that is far from the nucleus.

The first energy level (n = 1) can have maximum two electrons in it. The second energy level ( n= 2) can have maximum eight electrons and the third energy level can fill maximum eighteen electrons in it.

Learn more about energy levels, here:

https://brainly.com/question/17396431

#SPJ5

Answer:

B.9

Explanation:

Answer: I think that trains move faster then cars! Buttt, The trains are much stronger and bigger, then cars or trucks. Even if they move slowly they can still crush something smaller then them.

Explanation: ( didnt really understand the question, but i tried)

Answer:

23%

Explanation:

Answer:

45.9m

Explanation:

Given parameters:

Mass of the ball  = 1kg

Initial velocity  = 30m/s

Unknown:

Height the ball will travel  = ?

Solution:

At the maximum height, the final velocity of the ball  will be 0;

  Using ;

   V²   = U²   - 2gh

V is the final velocity

U is the initial velocity

g is the acceleration due to gravity

h is the height

     0² = 30²   - (2 x 9.8 x h)

    0 = 900 - 19.6h

      h  = 45.9m

Answer:

B. 6

Explanation:

Isotope given:

                      ¹⁴₆C

In specie written as this;  

  Superscript  = Mass number

  Subscript  = Atomic number

To find the protons, it is the same as the atomic number;

               Protons  = Atomic number  = 6

Neutrons have no charges;

Neutrons  = Mass number - Atomic number  =

 Neutrons  = 14 - 6  = 8

The number of electrons is the same as the atomic number = 6

Answer:

Explanation

whats your question

Answer:

I'd say about 8?

Explanation:

if you wanna make them huge make about 6

Answer:

Density, d = 8.92 g/mL

Explanation:

Let mass of the wooden block, m = 46.83  g

The volume of the object, V = 5.25 mL

We need to find the density of the wooden block. The density of an object is given by its mass per unit volume.

density = mass/volume

[tex]d=\dfrac{46.83\ g}{5.25\ mL}\\\\=8.92\ g/mL[/tex]

So, the density of the wooden block is 8.92 g/mL.

Answer:

0.495 g/cm3

Explanation:

Answer:

6

Explanation:

ye