is this true or false ?

Answer:

Various soft stones were employed, the most popular being lime- stone basalt.

Explanation:

Answer:My guess is the gravitational force between the objects or substances.

Answer:

A neon lamp was switched on during the Great Depression and continued to burn until it was discovered some 77 years later. The electricity bill came up to a whopping $17 000!

Explanation:

Answer:

Decrease

Explanation:

The lower you go, the colder because the sun can't reach lower levels of the ocean.

Answer:

decrease

Explanation:

less sunlight will be able to reach the farther down you go and the less sunlight there is the colder it gets

Answer:

Single replacement

Explanation:

Chemical equation:

2Al(NO₃)₃ + 3Ca    →    3Ca(NO₃)₂ + 2Al

Single replacement:

It is the reaction in which one elements replace the other element in compound.

AB + C → AC + B

All other options are incorrect because,

Double replacement:

It is the reaction in which two compound exchange their ions and form new compounds.

AB + CD → AD +CB

Synthesis reaction:

It is the reaction in which two or more simple substance react to give one or more complex product.

Decomposition reaction:

It is the reaction in which one reactant is break down into two or more product.

AB → A + B

Combustion reaction:

Reaction in substance react with oxygen and form carbon dioxide and water.

formula p=m/V

Explanation:

0.79

6.35

1.79

To find the density you have to divide the mass by volume

hope it helps!

A physical property is a characteristic of matter that is not associated with a change in its chemical composition. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity.

Answer:

they all have two electrons in their outermost shell

The elements of group 2 are alkaline earth metals that have two electrons in their outermost shell. So they have similar chemical and physical properties and tend to become positive ions in bond formation.

The elements present in group 2 include Beryllium, Magnesium, Calcium, Strontium, Barium, and Radium.  

The elements of group 2 are similar in their physical and chemical properties as all the elements have the same number of valence electrons. All alkaline earth metals are silvery-white-colored solids under normal conditions. They are also shiny and quite reactive.

The general electronic configuration of group 2 elements is ns². The alkaline earth metals have fully filled s-orbital in their valence shells, they tend to lose two electrons to produce cations with +2 charge.

Therefore, the elements of group 2 are electropositive in nature. Therefore, all the given statements about group 2 of the periodic table are true.

Learn more about elements of group 2, here:

https://brainly.com/question/20455446

#SPJ2

Answer:

P O 2 = 5.21 atm P C O 2 = 4.79 atm

Explanation:

Hope it helps!

Answer:

I believe the answer is A

Explanation:

I hope this helps :)

Answer:

0.01504 mol/dm3

Explanation:

Calcium Hydroxide - Ca(OH)2

Hydrochloric acid - HCl

The reaction between both is given as;

2HCl   +   Ca(OH)2   --> CaCl2  + 2H2O

2   :  1

The relationship between the concentration and volume is given as;

CaVa  /  CbVb = na  /  nb

where a = acid (HCl) and b = base Ca(OH)2

Inserting the values;

0.04 * 18.8  /  (Cb * 25)  =  2 / 1

0.752 / 25Cb = 2

Cb = 0.752 / 50  = 0.01504

Answer:

Law of conservation of mass

Ernest Rutherford

Explanation:

The basic law of behavior of matter that states that "mass is neither created nor destroyed in a chemical reaction or physical change".

This is the law of conservation of mass. It is very essential in understanding most chemical reaction. Also, in quantitative analysis, this law is pivotal.

Ernest Rutherford was the scientist that stated that the nucleus is made up of positive charge. It was not until James Chadwick in 1932 discovered the neutron that we had an understanding of this nuclear component.

Rutherford surmised from his experiment that because most the alpha particles passed through the thin Gold foil and just a tiny fraction was deflected back, the atom is made is made up of small nucleus that is positively charged.

Answer:

A is the answer it is correct

Answer:

A

Explanation:

trust me

Answer:

-water is collected from nearby water holes and put in a water tower after it's clean

Answer:

Your water comes from rivers and streams.

Explanation:

The water is collected from rivers and stream and gets delivered from the storage tank to the pipes of our house

Answer:

150

Explanation:

.5 liter increase every temperature  50°C.

5 liter= 50 C

5.5 liter= 100 C

6 liter= 150 C

Answer:

Ver explicación abajo

Explanation:

LA pregunta esta incompleta, pero logré conseguir un ejercicio muy parecido a este con datos similares, y la pregunta que falta como tal son estas:

"a) La cantidad de sal producida.

b)  Moléculas de hidrógeno obtenidas a 25 ºC y 740 mm Hg.

c)  El volumen de la disolución de ácido necesario para la reacción."

Asumiendo que estos son los datos faltantes, hay que ver como resolver por parte:

a) Cantidad de sal producida.

En este caso debemos plantear la reacción que se lleva a cabo. Es un mineral que tiene Zinc y reacciona con acido sulfurico, por tanto la reacción que se lleva a cabo en teoría es:

Zn + H₂SO₄ -----------> ZnSO₄ + H₂

Entonces, queremos saber la cantidad de ZnSO₄ que se formó.

Para eso, debemos calcular primero cuantos gramos de zinc hay originalmente en la muestra, que son los que reaccionaron para formar esta sal, y luego los moles para que por medio de estequiometría, calculemos los moles de la sal.

Para la masa de Zinc, sabemos que el mineral contiene 65% de zinc o 0,65 entonces:

mZn = 0,65 * 500 = 325 g

Calculamos los moles usando la masa molecular de Zinc que es 65,37 g/mol:

moles = 325 / 65,37 = 4.97 moles

Ahora bien, como la reacción de arriba está bien balanceada, podemos asuimr por estequiometría que la relación Zn / ZnSO₄ es 1:1, asi que los moles de Zn serán los mismos de la sal por tanto:

moles Zn = moles ZnSO₄ = 4,97 moles

Calculando la masa molecular de ZnSO₄:

MM ZnSO₄ = 65,37 + 32 + (16 * 4) = 161,37 g/mol

Finalmente la masa de la sal es:

m ZnSO₄ = 4,97 * 161,37

b) Moléculas de hidrógeno obtenidas

PAra este caso, ya tenemos los moles de Zn, y por estequiometría, todas las especies presentes están en relación 1:1, así que los moles de hidrógeno son los mismos de zinc. No es necesario el dato de temperatura y presión acá pues ya tenemos los moles.

Para conocer el número de moléculas, necesitamos el número de abogadro que es 6.02x10²³ por lo tanto las moléculas de hidrógeno:

Moléculas de hidrógeno = 6,02x10²³ * 4,97

c) Volúmen de ácido empleado

Finalmente para el ácido, como ya conocemos los moles empleados, podemos calcular la masa del ácido usando su peso molecular:

MM H₂SO₄ = (2*1) + 32 + (4*16) = 98 g/mol

m H₂SO₄ = 4,97 * 98 = 487,06 g

Ahora que ya sabemos su masa, solo calculamos la masa realmente usada (pues su %p/p es 96%) y con la densidad calculamos el volumen:

d = m/v

v = m/d

m H₂SO₄ (puro) = 487,96 * 0,96 = 467,58 g

El volumen será:

V = 467,58 g / 1,823

Espero que esto te sirva, o te ayude como impulso a tu ejercicio real.

Answer:

C. both particle and a wave

Answer: C. Both a Particle and a Wave

Explanation:

Light can travel as particles or like waves. We can see it traveling like particles when a firefly glows. That is still a version of light. It travels as a wave when you turn on your light, faster than sound can. These are the two versions of light, particle and wave. The answer is C. Both a Particle and a Wave

Answer:

b.) potential energy was transformed into kinetic energy

Explanation:

According to the law of conservation of energy, energy is neither created nor destroyed but transformed from one form to another in a system.

So, in this system, energy is not created neither is it destroyed.

Answer:

Explanation:

The reactivity of elements in the periodic table is based on the number of electrons in there outermost shell. Elements (metals) that have few electrons in there outermost shell are highly reactive because it is easier to lose fewer number of electrons (in the outermost shell during a reaction) than to lose more electrons in the outermost shell - thus metals that have one electron in there outermost shell are most reactive and are more reactive than those that have two electrons in there outermost shell. Hence, metals in group 1 are the most reactive metals because they all have one electron in there outermost shell.

Non-metals that have fewer electrons to complete there octet configuration are highly reactive because it is easier to gain fewer number of electrons (in the outermost shell during a reaction) than to gain more number of electrons - thus nonmetals that have seven electrons in there outermost shell are more reactive than nonmetals that have six electrons in there outermost shell. Hence, nonmetals in group 17 are the most reactive nonmetals because they contain seven electrons and have just one electron left to complete there octet configuration.

Answer:

yes

Explanation:

Answer:

melting evaporation

Explanation:

melting decreases because its melting out of form

Answer:the answer should be A E and F

Explanation:

They all use decreased energy

Answer:

A

Explanation:

Because it does not change entirely.

Answer:

if you search up the periodic table and go to any website it will let you press on the element and it will say if it is a gas,solid or liquid and it might say if it is man made!

Explanation:

i really hope this helps:)

Answer:

3.56x10²³ atoms

Explanation:

To solve this question we need first to determine the moles of iron (II) chloride, FeCl₂, using its molar mass. Then, using Avogadro's number we can solve for the number of atoms:

Moles FeCl₂ - Molar mass: 126.751g/mol-

25g FeCl₂ * (1mol / 126.751g) = 0.1972 moles

Number of atoms:

1 mole of FeCl₂ are 6.022x10²³ molecules of FeCl₂, that means 0.1972moles are:

0.1972mol * (6.022x10²³ molecules / 1mol) = 1.188x10²³ molecules of FeCl₂

In 1 molecule of FeCl₂ there are 3 atoms (1 of Fe and 2 of Cl), in 1.188x10²³ molecules of FeCl₂ there are:

1.188x10²³ molecules of FeCl₂ * (3atoms / molecule) =

Answer:

The viscosity of intestinal contents should define the mixing, diffusion and flow of nutrients and other materials in digesta (1–4). The viscosity of intestinal contents has been measured only after the removal of solid particles by centrifugation (5,6), under the assumption that particles or insoluble fibers in the diet do not affect the viscosity of gut contents (7). However, the complete removal of solid particles considerably reduced the coefficient of viscosity of pig cecal contents and changed the contents from a non-Newtonian to a Newtonian fluid in our recent study

Answer:

A

Explanation:

This is the answer because:

Rainfall highly helps the trees on the mountains grow. The location of a tree also matters a lot because it has to be in a spot where it can reach sunlight and lots of rain.

Therefore, the answer is A.

Hope this helps! :D

Answer:

One oxygen atom I think..as C10 is 10 atoms of carbon, and H20 is two atoms of hydrogen with one atom of oxygen

Explanation:

Answer: Well,diffusion does not happen in solids because the particles are not free to move around and so they cannot inter-mix.