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3 years ago

Alpha particles are helium nuclei. electromagnetic waves. electrons. neutrons.

1 answer:

4 0

Alpha particles are helium nucleus ! so answer is A !

it is made by ionization of helium, when both the electrons are out , then two unit of positive charge is one helium and thus called alpha particle !

You might be interested in

What type of reaction will occur with the following reactants?

zalisa [80]

Answer:

A) double replacement

Explanation:

Chemical equation:

NaCl +CaS → Na₂S + CaCl₂

Balanced chemical equation:

2NaCl +CaS → Na₂S + CaCl₂

The given reaction is double replacement reaction in which cation and anions of each reactant exchange with each other.

Double replacement:

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

AB + CD → AD +CB

Other options are incorrect because,

Synthesis reaction:

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

AB → A + B

Single replacement:

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

AB + C → AC + B

Decomposition reaction:

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

AB → A + B

6 0

3 years ago

A compound is 7.74% hydrogen and 92.26% carbon by mass. At 100°C a 0.6883 g sample of the gas occupies 250 mL when the pressure

ycow [4]

Answer: The molecular formula for the compound is $C_6H_6$

Explanation:

We are given:

Percentage of C = 92.26 %

Percentage of H = 7.74 %

Let the mass of compound be 100 g. So, percentages given are taken as mass.

Mass of C = 92.26 g

Mass of H = 7.74 g

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{92.26g}{12g/mole}=7.68moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{7.74g}{1g/mole}=7.74moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 7.68 moles.

For Carbon = $\frac{7.68}{7.68}=1$

For Hydrogen = $\frac{7.74}{7.68}=1$

Step 3: Taking the mole ratio as their subscripts.

The ratio of C : H = 1 : 1

The empirical formula for the given compound is $CH$

Calculating the molar mass of the compound:

To calculate the molecular mass, we use the equation given by ideal gas equation:

PV = nRT

Or,

$PV=\frac{m}{M}RT$

where,

P = pressure of the gas = 820 torr

V = Volume of gas = 250 mL = 0.250 L (Conversion factor: 1 L = 1000 mL )

m = mass of gas = 0.6883 g

M = Molar mass of gas = ?

R = Gas constant = $62.3637\text{ L. torr }mol^{-1}K^{-1}$

T = temperature of the gas = $100^oC=(100+273)K=373K$

Putting values in above equation, we get:

$820torr\times 0.250L=\frac{0.6883g}{M}\times 62.3637\text{ L torr }mol^{-1}K^{-1}\times 373K\\\\M=\frac{0.6883\times 62.3637\times 373}{820\times 0.250}=78.10g/mol$

For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.

The equation used to calculate the valency is:

$n=\frac{\text{Molecular mass}}{\text{Empirical mass}}$

We are given:

Mass of molecular formula = 78.10 g/mol

Mass of empirical formula = 13 g/mol

Putting values in above equation, we get:

$n=\frac{78.10g/mol}{13g/mol}=6$

Multiplying this valency by the subscript of every element of empirical formula, we get:

$C_{(1\times 6)}H_{(1\times 6)}=C_6H_6$

Hence, the molecular formula for the compound is $C_6H_6$

8 0

3 years ago

How many of the organisms represented are multicellular

kari74 [83]

Son organismos que pertenecen al Nivel de Organización Protoplasmático. Son UNICELULARES y se distinguen por no poseer un Núcleo bien organizado. Son PROCARIOTAS porque el material genético (ADN o Cromosomas) al no tener Carioteca o Membrana Nuclear, se encuentran dispersos en el Citoplasma. Comprenden a las Cianofíceas y Bacterias. Las Cianofíceas o Algas verde azuladas son Autótrofos, ya que realizan la Fotosíntesis y algunas Bacterias se nutren por Absorción, ya sea descomponiendo a sustratos orgánicos como las Saprófitas, o infectando a un organismo vivo y viviendo a expensas de él como las Parásitas y otras son Heterótrofas y Autótrofas. Poseen un Sistema de Nutrición AUTÓTROFA, HETERÓTROFA y por ABSORCIÓN. Las Bacterias son Células muy pequeñas, que tienen Reproducción Asexual por Fisión Binaria. Tienen Pared Celular porosa. Presentan diferentes Formas (Cocos, Bacilos, Espirilos, Vibriones). Producen Enfermedades (Tuberculosis, Lepra, Sífilis, Neumonia, etc.) Hay Bacterias Beneficiosas (Producción de alcohol y vinagre, quesos, yogurth, etc.). Las CIANOBACTERIAS poseen CLOROFILA y un Pigmento azul llamado FICOCIANINA. Pueden estar libres o en colonias.

5 0

3 years ago

A 623 ml sample of gas at STP is allowed to expand (like the universe) until it

RSB [31]

12000 ml would be d to my calculations but then u can 12

7 0

3 years ago

What is the chemical formula for the compound formed between sodium and iodine?

IrinaK [193]

Each compound will be neutral

6 0

3 years ago