Which of these is the subject of study in thermodynamics? a) energy changes b) only physical changes 3) only chemical changes 4) structure of atoms and molecules

Answer:

the answer is stem please mark me as brainlist

The compound is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions.

(I hope this helped ^^)

Ionic compounds can be defined as a neutral compound composed of protons and electrons. Thus option C is correct.

An ionic compound has been formed by the transfer of electrons between atoms. The transfer of electrons will impose a charge on the atoms involved in the bond, and result in an ionic compound.

The interaction of the positively charged cations and negatively charged anions takes place. The protons are the positive charged species and electrons are the negatively charged species.

Thus, the ionic compound has been a neutral compound formed by protons and electrons. Thus option C is correct.

For more information about ionic compounds, trefer to the link:

https://brainly.com/question/9167977

Answer:

A. Potassium (K)

Explanation:

The trend of atomic radius goes:

As group number increases, radius decreases

As period number increases, radius increases

Answer:

francium

Explanation:

Atomic radii vary in a predictable way across the periodic table. As can be seen in the figures below, the atomic radius increases from top to bottom in a group, and decreases from left to right across a period. Thus, helium is the smallest element, and francium is the largest.

Answer:

I think it would take her 25 Seconds

Explanation:

To calculate how long it would take for Sarah, I did 200 divided by 8. When I did that, I got 25 as my answer. I'm not exactly sure if it would be in seconds or minutes, but I feel that seconds is more reasonable. I hope this helps, and I hope it's not wrong, but I do not think it is.

Answer:

In other words, atoms of one element can be changed into atoms of another element by transmutation. This occurs either through nuclear reactions in which an outside particle reacts with a nucleus, which can be supplied by a particle accelerator, or through radioactive decay, where no outside particle is needed.

Answer:

Bill of materials

Explanation:

Answer:

There are 2.81 * 10^24 atoms present

Explanation:

To get this, we need to know the number of moles present in 140gramms of carbon.

Mathematically;

number of moles = mass/molar mass

molar mass of glucose is = 180 g/mol

So the number of moles will be ;

140/180 = 0.7778 mole

1 mole of glucose contains 6 moles of carbon;

so 0.7778 moles will contain = 4.667 moles

Mathematically, the number of atoms in 1 mole is 6.02 * 10^23 atoms

The number of atoms in 4.667 moles will be :

4.667 * 6.02 * 10^23 = 2.81 * 10^24 atoms

Answer:

Explanation:

The new pressure can be found by using the formula for Boyle's law which is

[tex]P_1V_1 = P_2V_2[/tex]

where

P1 is the initial pressure

P2 is the final pressure

V1 is the initial volume

V2 is the final volume

Since we are finding the new pressure

[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]

So we have

[tex]P_2 = \frac{95 \times 34}{55} = \frac{3230}{55} \\ = 58.72727272...[/tex]

We have the final answer as

Hope this helps you

Answer:

I think it's D, cicada.

According to Oxford, a Hemipteran is "an insect of the order Hemiptera, such as an aphid, cicada, or leafhopper."

Hope this helps! I also hope it's not wrong, but I do not think it is.

Also please let me know if this is correct.

Answer: you would hace to adapt to the climate

Explanation:

Answer: Migration and hibernation are examples of behavioral adaptations used by animals in the Arctic tundra. The fact that many animals do not live year-round in the tundra means they leave or migrate for a length of time to warmer climates.

Answer:

2 valence electrons.

Explanation:

Valence electrons are the sum total of all the electrons in the highest energy level (principal quantum number n). Most transition metals have an electron configuration that is  

n

s

2

(

n

−

1

)

d

, so those  

n

s

2

electrons are the valence electrons

Answer:

84

Mass = moles x molecular mass of LiOH

         = 3.5 x 24

         = 84 g/mol

Answer:

Magnesium (Mg)

Explanation:

Beryllium has an atomic number of 4

4 times 3 is 12

Magnesium has an atomic number of 12

The quantity of heat : 226,000 J

Heat can be calculated using the formula:  

Q = mc∆T  

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

Q = m. Hf

Hf = heat of fusion

Heat required for vaporize /evaporated can be calculated from

Q = m . Hv

m = mass, g

Hv = the heat of vaporization, for water = 2,260 J/g

So :

[tex]\tt Q=100\times 2,260=226,000 J[/tex]

Answer:

population growth increases.

Answer:

B = 6.06 g

Explanation:

Chemical equation:

2Al + 6HCl     →     2AlCl₃ + 3H₂

In given balance chemical equation there are 3 moles of hydrogen are formed.

Mass of hydrogen in gram:

Formula:

Number of moles = mass/molar mass

Mass = number of moles × molar mass

Molar mass of hydrogen = 1.008×2 = 2.016 g/mol

Mass = 2.016 g/mol× 3 mol

Mass = 6.05 g

It is almost equal to 6.06 g thus option B is correct.

Answer: 6.06

Explanation:

Answer:

Sodium bicarbonate or baking soda

Explanation:

Answer:

Im pretty sure its Cl but that might be wrong

Explanation:

I looked on the web for this one

Answer:

Explanation:

The work done by an object can be found by using the formula

From the question we have

workdone = 15 × 3

We have the final answer as

Hope this helps you

Answer:

Are fluffy.

Explanation:

Cumulus clouds are clouds which have flat bases and are often described as "puffy", "cotton-like" or "fluffy" in appearance. Their name derives from the Latin cumulo-, meaning heap or pile. ... Cumulus clouds may appear by themselves, in lines, or in clusters.

Answer:

See explanation

Explanation:

From the statement of the first law of thermodynamics, energy is neither created nor destroyed, but is transformed from one form to another.

Thermal energy is possessed by the hot air while the fire is burning. This  thermal energy was obtained from the chemical energy stored in carbohydrates(cellulose) that is present in wood material. As the combustion proceeds, chemical energy stored in chemical bonds of the wood material converts into thermal energy (heat energy). The chemical reaction involved in the combustion of wood can be simplified as shown below; n represents the number of glucose units that combine to make up the cellulose present in the wood material.

nC6H12O6(s) + 6nO2(g) ===> 6nCO2(g) + 6nH2O(g)

n may even be as much as thousands of glucose units.

Answer:

The electrostatic attraction energy between ions of opposite charge is directly proportional to the charge on each ion (Q 1 and Q 2 in Equation 4.1. 1). Thus, more energy is released as the charge on the ions increases(assuming the internuclear distance does not increase substantially).

Answer:

single or double covalent bonds

Explanation:

Rain occurs when water vapor _condensates____.

sorry if I'm wrong

Answer:

turns into clouds it cools and condenses

Explanation:

a. K Na Li

melting point decreases a

down the group since more shells are added down the group hence the the attractive force that the protons exert on the electrons decreases down the group and hence melting point also decreases down the group.

i.e Li,Na,K decreasing order.

And hence the increasing order will be:

K Na Li.

b. Na Mg Al

Effective nuclear charge increases across the period and hence melting point increases across the period since Al Mg and Na are in the same period hence the increasing order will be Na Mg Al.

Answer:

a. K,Na,Li

b. Na,Mg,Al

Explanation:

the first one Lithium because it has small atomic size hence their is greater attraction for the electrons in the energy level ,hence the heat required to break the bond is a lot hence high melting point

the second one Aluminium has a higher mpt than Mg and Na this is because as u go along the period the nuclear charge increases hence exerts higher attraction towards the electrons in the energy levels hence the bond formed is strong hence will require more heat to break.

Answer:

true

Explanation:

negatively charged electrons are affected by the magnetic field.

Answer:

false

Explanation:

It isn't affected because nothing makes it change and the number stays the same

Answer:

D

Explanation:

Solid , Liquid and Gas

Answer:

D. liquid, gas, and solid

Hope I helped!

Explanation:

sedimentary rocks are rocks that are combined from other rocks pressed into one.