Complete the following radioactive decay problem. Please help

Answer:

Advantage:

It forms ferrous oxide which is used as a pigment for glasses

Disadvantage:

It destroys the appearance of the metal and weakens it.

Answer:

Advantage: Rusting provides a thin durable shell to prevent the metal from getting more corroded.

Disadvantage: Rusting weakens material due to prolonged corrosive action.

Explanation:

Answer:

Iron is oxidized to form rust.

Explanation:

Consider the reaction; 4Fe + 302------>2Fe2O3, we can see that iron is being oxidized to iron III oxide. Rust is the common name of iron III oxide.

Rusting is an electrochemical process, iron rusts when it comes into contact with air and water because electrochemical cells are set up at the surface of contact.

Iron usually functions as the anode in the electrochemical process. This process leads to the formation of iron III oxide. Rust is soft and breaks off easily thereby exposing the metal below the surface to further rusting.

Answer:

Iron is oxidized to form rust.

Explanation:

edge

Answer:

1) 60°

2) 60°

3) 45°

4) E

5)90°

6) E

Answer:

d

Explanation:

its not a b c

Answer:

the answer would be 2

Explanation:

Answer:

B. H2SO4 + BaCl 2 --------> BaSO4 + 2HCl

Explanation:

Neutralization reactions are characterized by their reactants of acids and bases reacting to form salt and water. All of the options except B, have formation of salt and water. Also, B is more likely a percipitation reaction (also a double displacement reaction) and not neutralization.

Answer:

[tex]\large \boxed{0.012 \%}[/tex]

Explanation:

Data:

Solution 1: V₁ =   50.0 mL; c₁ = 0.05 mol·L⁻¹

Solution 2: V₂ = 100   mL; c₂ = 0.02 mol·L⁻¹

NaCl         :   ρ =     2.1 g/mL  

1. Solution 1

(a) Moles of NaCl

[tex]n = \text{50.0 mL} \times \dfrac{\text{0.05 mmol}}{\text{1 L}} = \text{2.5 mmol}[/tex]

(b) Mass of NaCl

[tex]m = \text{2.5 mmol} \times \dfrac{\text{58.5 mg}}{\text{1 mmol}} = \text{150 mg} = \text{0.15 g}[/tex]

(c) Volume of NaCl

[tex]V = \text{0.15 g} \times \dfrac{\text{1 mL}}{\text{2.1 g}} = \text{0.070 mL}[/tex]

(d) Volume of water

V = 50.0 mL - 0.070 mL = 49.9 mL

(e) Mass of water

[tex]\text{Mass} = \text{49.9 mL} \times \dfrac{\text{1.00g}}{\text{1 mL}} = \text{49.9 g}[/tex]

2. Solution 2

(a) Moles of NaCl

[tex]n = \text{100 mL} \times \dfrac{\text{0.02 mmol}}{\text{1 mL}} = \text{2.0 mmol}[/tex]

(b) Mass of NaCl

[tex]m = \text{2.0 mmol} \times \dfrac{\text{58.5 mg}}{\text{1 mmol}} = \text{120 mg} = \text{0.12 g}[/tex]

(c) Volume of NaCl

[tex]V = \text{0.12 g} \times \dfrac{\text{1 mL}}{\text{2.1 g}} = \text{0.053 mL}[/tex]

(d) Volume of water

V =100 mL - 0.055 mL = 100 mL

(e) Mass of water

[tex]\text{Mass} = \text{100 mL} \times \dfrac{\text{1.00 g}}{\text{1 mL}} = \text{100 g}[/tex]

3. Combined solutions

(a) Mass of NaCl

Mass of NaCl = 0.015 g + 0.012 g = 0.018 g

(b) Mass of water

Mass of water = 49.9 g + 100 g = 150 g

(c) Mass percent

[tex]\text{Mass percent} = \dfrac{\text{Mass of component}}{\text{Total mass}} \times \, 100 \,\%\\\\\text{Mass \% NaCl} = \dfrac{\text{0.018 g}}{\text{150 g}}\times \, 100 \% = \mathbf{0.012 \%}\\\\\text{The mass percent of NaCl is $\large \boxed{\mathbf{0.012 \, \%}}$}[/tex]

Answer:

1.507 moles of CO₂ are released daily by a hummingbird's respiration

Explanation:

The reaction of production of carbon dioxide and water from sugar is:

C₁₂H₂₂O₁₁ + 12O₂ → 12CO₂ + 11H₂O

Where 1 mole of sugar produce 12 moles of CO₂

Molar mass of sugar (To convert the mass to moles) is:

12C = 12ₓ12.01g/mol = 144.12g/mol

22H = 22ₓ1.01g/mol = 22.22g/mol

11O = 11ₓ16g/mol = 176g/mol

144.12 + 22.22 + 176 = 342.34g/mol

Thus, moles of 43.0g of sugar are:

43.0g ₓ (1mol / 342.34g) = 0.1256 moles of sugar.

As 1 mole of sugar produce 12 moles of CO₂:

0.1256 moles of sugar ₓ (12 moles CO₂ / 1 mol sugar) =

Answer:

m = 50.74 kg

Explanation:

We have,

Initial temperature of water is 20 degrees Celsius

Final temperature of water is 46.6 degrees Celsius

Heat absorbed is 5650 J

It is required to find the mass of the sample. The heat absorbed is given by the formula ad follows :

[tex]Q=mc\Delta T[/tex]

c is specific heat of water, c = 4.186 J/g°C

So,

[tex]m=\dfrac{Q}{c\Delta T}\\\\m=\dfrac{5650}{4.186\times (46.6-20)}\\\\m=50.74\ kg[/tex]

So, the mass of the sample is 50.74 kg.

Answer:

80.07 g/mol

Explanation:

Sulfur's g/mol = 32.07

Oxygen's g/mol = 16.00

32.07 + 16.00(3) = 80.07 g/mol

Answer:

80.07 g/mol

Explanation:

Answer:

trimolecular

Explanation:

Answer:

They assumed they both had water.

Explanation:

Because they only could look at it through telescopes that were not advanced

Answer:

D.

Explanation:

In a Galvanic cell:

1) Spontaneous reactions take place

2) Chemical Energy is converted to some useful electrical energy

Answer:

ammonium ferric citrate and

potassium ferricyanide

Answer:

ammonium ferric citrate and potassium ferricyanide

Answer:

1.68 atm.

Explanation:

Given:

P1 = 4.23atm

V1 = 1870 mL

T1 = 293K

P2 = ?

V2 = 6.01 L = 6010 mL

T2 = 373 K

Assuming number of moles and R is constant:

[tex]\frac{P1V1}{T1} = \frac{P2V2}{T2}[/tex]

⇒ P2 = [tex]\frac{P1V1T2}{T1V2}[/tex] = [tex]\frac{2,950,467.3}{1,760,930}[/tex]

= 1.68 atm.

Answer:

thats the answer

Explanation:

Answer:

Explanation:

En este caso para formular los compuestos, debes identificar el grupo funcional principal de la molecula. Una vez que eso está hecho, puedes intentar formularlo.

Empezaremos primero identificando el grupo funcional principal de la molécula, para luego formularlo correctamente.

Dietil eter: la terminación eter al final significa que pertenece al grupo de los éteres, el cual tiene como formula general R - O - R.

Etanol: debido a que termina en ol, este grupo pertenece a los alcoholes. Para formularlo solo se dibuja la molecula del etano, junto a un enlace con el grupo OH, como su formula general R - OH.

Propanotriol: igualmente termina en ol, por lo tanto es un alcohol, sin embargo, en este caso, tambien tiene la terminación prefija tri, asi que significa que hay 3 grupos OH en la molecula.

Acido propanodioico: esta es sencilla, porque empieza como acido, y solo hay un grupo funcional que empieza así y son los acidos carboxilicos, es decir, el grupo COOH (R - COOH) que es el carboxilo. Tiene el prefijo di, antes del oico, por lo que son dos carboxilos presentes en la molecula.

Pentanal: el sufijo al, significa que pertenece al grupo de los aldehidos, en este caso, posee el grupo carbonilo H - C = O.

Pentano - 2,4 - diona: la terminación ona significa que pertenece al grupo de las cetonas, (R - CO - R), parecido a los aldehidos, con la diferencia de que tiene grupos alquilos en lugar de un hidrogeno.

Metanoato de metilo: la terminación ato de ilo, pertenece a los esteres, (R - COOR) derivado de los acidos carboxilicos.

De aqui en adelante solo mencionaré los grupos funcionales pues ya se explicó el por que, por sus terminaciones:

Ciclohexano - 1.3 - diol: este pertenece a los alcoholes.

Acido heptanoico: acido carboxilico

Ciclobutil metil eter: eteres

Acetato de etilo: ester

2-metilbenzaldehído: aldehído unido a un grupo aromatico como el benceno.

Ciclohexanona: un ciclo (cadena cerrada) unido a un grupo carbonilo.

Butanona: cetona.

Observa la foto adjunta para que veas la formulación de cada una:

Answer:

Mineral water> Bitter gourd juice> Orange juice> Hydrochloric acid

Explanation:

pH is referred to as the degree of acidity or alkalinity of a substance. The pH scale is arranged from 0-14. Substance with a pH of 0-6.9 are acid, a pH of 7 indicates neutrality while a pH of 8-14 indicates alkalinity.

Mineral water is usually slightly acidic with a pH between 5-6. The pH of bitter gourd juice is between 4.24-4.45. The pH of orange juice ranges between 3.3 to 4.2 lastly, the pH of hydrochloric acid is about 3.01.

The pH values itemized above informed the arrangement of decreasing pH values shown in the answer box.

Answer:

The Valence electrons in S

Explanation:

Sulphur has highest effective nuclear charge as in a period there is increase in effective nuclear charge from left to right.Sulphur is in the end in a period leaving Mg and Al in left side.

Hope this helps....

Good luck on your assignment...

pH = 0.35

Explanation: hope this helps

Answer: 0.35

Explanation:

Answer:

atoms and molecules

Explanation:

matter is made up of particles called atoms and molecules

Matter is made up of small molecules and attoms

Answer:

A

Explanation:

Answer:

Sodium sulfide is the chemical compound with the formula Na2S, or more commonly its hydrate Na2S·9H2O. Both the anhydrous and the hydrated salts are colorless solids. They are water-soluble, giving strongly alkaline solutions. When exposed to moist air, Na2S and its hydrates emit hydrogen sulfide, which smells like rotten eggs. Some commercial samples are specified as Na2S·xH2O, where a weight percentage of Na2S is specified. Commonly available grades have around 60% Na2S by weight, which means that x is around 3. Such technical grades of sodium sulfide have a yellow appearance owing to the presence of polysulfides. These grades of sodium sulfide are marketed as 'sodium sulfide flakes'.

Contents

1 Structure

2 Production

3 Reactions with inorganic reagents

4 Uses

4.1 Reagent in organic chemistry

5 Safety

6 References

Structure

Na2S adopts the antifluorite structure,[2][3] which means that the Na+ centers occupy sites of the fluoride in the CaF2 framework, and the larger S2− occupy the sites for Ca2+.

Production

Industrially Na2S is produced by carbothermic reduction of sodium sulfate often using coal:[4]

Na2SO4 + 2 C → Na2S + 2 CO2

In the laboratory, the salt can be prepared by reduction of sulfur with sodium in anhydrous ammonia, or by sodium in dry THF with a catalytic amount of naphthalene (forming sodium naphthalenide):[5]

2 Na + S → Na2S

Reactions with inorganic reagents

The sulfide ion in sulfide salts such as sodium sulfide can incorporate a proton into the salt by protonation:

S2−

+  H+ → SH−

Because of this capture of the proton ( H+), sodium sulfide has basic character. Sodium sulfide is strongly basic, able to absorb two protons. Its conjugate acid is sodium hydrosulfide (SH−

). An aqueous solution contains a significant portion of sulfide ions that are singly protonated.

S2−

+ H

2O {\displaystyle {\ce {<=>>}}}{\displaystyle {\ce {<=>>}}} SH−

+  OH−

(1)

SH−

+ H

2O {\displaystyle {\ce {<<=>}}}{\displaystyle {\ce {<<=>}}} H

2S +  OH−

(2)

Sodium sulfide is unstable in the presence of water due to the gradual loss of hydrogen sulfide into the atmosphere.

When heated with oxygen and carbon dioxide, sodium sulfide can oxidize to sodium carbonate and sulfur dioxide:

2 Na2S + 3 O2 + 2 CO

2 → 2 Na2CO3 + 2 SO2

Oxidation with hydrogen peroxide gives sodium sulfate:[6]

Na2S + 4 H2O2 → 4 H

2O + Na2SO4

Upon treatment with sulfur, polysulfides are formed:

2 Na2S + S8 → 2 Na2S5

Uses

Sodium sulfide is primarily used in the kraft process in the pulp and paper industry.

It is used in water treatment as an oxygen scavenger agent and also as a metals precipitant; in chemical photography for toning black and white photographs; in the textile industry as a bleaching agent, for desulfurising and as a dechlorinating agent; and in the leather trade for the sulfitisation of tanning extracts. It is used in chemical manufacturing as a sulfonation and sulfomethylation agent. It is used in the production of rubber chemicals, sulfur dyes and other chemical compounds. It is used in other applications including ore flotation, oil recovery, making dyes, and detergent. It is also used during leather processing, as an unhairing agent in the liming operation.

Reagent in organic chemistry

Alkylation of sodium sulfide give thioethers:

Na2S + 2 RX → R2S + 2 NaX

Even aryl halides participate in this reaction.[7] By a broadly similar process sodium sulfide can react with alkenes in the thiol-ene reaction to give thioethers. Sodium sulfide can be used as nucleophile in Sandmeyer type reactions.[8] Sodium sulfide reduces1,3-dinitrobenzene derivatives to the 3-nitroanilines.[9] Aqueous solution of sodium sulfide can be refluxed with nitro carrying azo dyes dissolved in dioxane and ethanol to selectively reduce the nitro groups to amine; while other reducible groups, e.g. azo group, remain intact.[10] Sulfide has also been employed in photocatalytic applications.[11]

Explanation:there you go

When sodium combines with sulphur, it formed sodium sulphide. When it interacts with sulfur, polysulfides are produced. Additionally, heat causes sodium sulfide to oxidize fast. Sulfur dioxide and sodium carbonate are the end products.

Chemical element sulfur has the letter S and atomic number 16. It is multivalent, nonmetallic, and plentiful. Sulfur atoms normally combine to create cyclic octatomic molecules, which have the chemical formula S₈.

At room temperature, elemental sulfur is a crystalline solid that is brilliant yellow. It is employed in the production of fertilizer, water treatment, mineral extraction, oil refining, and automobile batteries.

Other uses for compounds based on sulfur include vulcanizing rubber, bleaching paper, and producing goods like cement, detergents, and insecticides.

Thus, When sodium combines with sulphur, it formed sodium sulphide.

To learn more about sulphur follow the link;

https://brainly.com/question/19511790

#SPJ6

Answer:

the correct choice would be: 4. Reaction rates are not related to spontaneity.

Explanation:

The speed of reaction is independent of spontaneity, since it depends on other factors such as the amount of reagent.

The amount of reagent is one of the variables that most influences the speed of reaction, the greater the amount of reagent, the faster the reaction will be and thus the speed will be increased.

Answer:

split the reaction in to respective ions to ge the ionic equation of this reaction

Explanation:

2 Al + 2Fe+3  O3^-2 ---> 2Al+3 O3^-2  + 2Fe

ins simple it would be

Al   + Fe+3     ----> Al+3   + Fe

Answer:

Genetic tagging, or the identification and tracking of individual animals using DNA, is a non-invasive method of conducting research that uses samples from shed hair, feathers, feces, or saliva. ... Genetic tagging approaches are complementary to traditional approaches and add a powerful tool to the ecologists' toolkit."

Explanation:

Answer:

1) H2

2) Chlorine

3) Lead bromide

What is pollen in the reproduction cycle of flowering plants?

A pollen grain is a microspore containing the male gametophyte, usually reduced to two undivided cells, each with one haploid (n) nucleus. These cells are surrounded by a very resistant wall, the exine, which generally has apertures, zones with less resistance which will allow the germination of the pollen tube.

Explanation of the reproduction cycle (cf diagram above)

A given species produces flowers bearing stamens. According to species, these flowers can be unisexual (stamens only) or bisexual (stamens and carpels).

The stamen anthers include 4 pollen sacs containing sporogenous cells (diploid=2n). These sporogenous cells undergo meiosis, each producing 4 microspores (haploid=n). Two nuclei are then formed by mitosis : the vegetative nucleus and the generative nucleus. The latter divides to form 2 sperms. Simultaneously the wall of the microspores becomes thicker and takes the characteristic shape of the species : it is a pollen grain (see: What are the morphological characteristics of pollen and spore grains?). In the majority of species, the 4 grains (resulting from the 4 microspores) split up into single grains; in some cases, they remain together (tetrad = group of 4 grains). When mature, pollen grains are released by the opening of the anthers.

A pollen grain is aimed at reaching another flower of the same species, bearing carpels. The ovaries contain ovules, in which meiosis occurs, then mitoses. It results in an embryo sac with 8 nuclei, among which an egg cell and 2 central cells. When a pollen grain arrives on another flower (see : How are the spores and pollen grains transported?), it is received by the stigmas.

The pollen grain germinates through an opening of the wall: the vegetative nucleus develops into a pollen tube which is guided by the style to the ovary, then enters the micropyle of an ovule. The pollen tube releases 2 sperm nuclei into the ovule: one of the sperms fuses with the egg cell into a zygote (2n), while the other sperm fuses with central nuclei and gives rise to albumen (= food source). There are generally several ovules in an ovary : each one can be fertilized by a distinct pollen grain.

Each fertilized ovule and its albumen form a seed that will develop into a new individual of this species. hope it works

Answer:

pollen

Explanation:

you insolent vacuum