probably the first metal to be freed from its ore by smelting was

Answer:

Carbonic acid in ocean waters dissolves calcium carbonate that forms coral reefs.

Explanation:

I took the quiz and got it right

The acid rain is toxic to vegetation and aquatic life. The elements like calcium or magnesium can act as the buffer which neutralize the acid rain.

The normal pH of rain water is 5.6 due to the formation of H⁺ ions from the reaction between CO₂ and water. When it drops below 5.6, it is called acid rain. Leather, paper, etc. are disintegrated by the acid rain.

The oxides of sulphur and nitrogen, phosphoric acid present in the polluted air dissolve in rain water making it more acidic. SO₂ and NO₂ are the major contributors of acid rain.

The rocks with high amounts of calcium like limestone and dolomite are effective in lowering the acidity of water from precipitation which infiltrates underground. In places with soils having calcium, the effect of acid rain can be held by keeping the pH of ground water to remain near neutral or alkaline.

Thus limestone neutralize acid rain.

To know more about acid rain, visit;

https://brainly.com/question/28176597

#SPJ2

The temperature change is 60°C

A temperature change occurs when temperature is increased or decreased by the flow of heat.

This shifts chemical equilibrium toward the products or reactants, which can be determined by studying the reaction and deciding whether it is endothermic or exothermic.

The material was cooled from 100°C to 40°C

The temperature change can be calculated as

ΔT = 100°-40° = 60°C

To know more about Temperature Change

https://brainly.com/question/19051558

#SPJ4

Answer:

phosphorus

Explanation:

Answer:

phosphorus

Explanation:

phosphorus has to lose electrons

Answer:

Extensive properties, such as mass and volume, depending on the amount of matter being measured. Intensive properties, such as density and color, do not depend on the amount of the substance present. Physical properties can be measured without changing a substance's chemical identity.

Explanation:

Answer:

380 mL

Explanation:

A chemist must prepare 925 mL of 325 mM aqueous copper(II) sulfate working solution. He'll do this by pouring out some 0.792 M aqueous copper(II) sulfate stock solution into a graduated cylinder and diluting it with distilled water. Calculate the volume in mL of the copper(II) sulfate stock solution that the chemist should pour out. Be sure your answer has the correct number of significant digits.

Step 1: Given data

Step 2: Convert "C₂" to M

We will use the conversion factor 1 M = 1000 mM.

325 mM × (1 M/1000 mM) = 0.325 M

Step 3: Calculate the inital volume

We will use the dilution rule.

C₁ × V₁ = C₂ × V₂

V₁ = C₂ × V₂/C₁

V₁ = 0.325 M × 925 mL/0.792 M

V₁ = 380 mL

The enthalpy change needed for one mole of a substance to freeze is the opposite of the enthalpy change for melting, but with the same magnitude. Therefore, the enthalpy change for freezing would be ΔH = +79 kJ/mol. Option B.

When a substance melts, it absorbs heat from its surroundings, which leads to an increase in the enthalpy of the system. This increase in enthalpy is represented by a negative value for the enthalpy change, indicating an endothermic process. In this case, the given enthalpy change for melting is ΔH = -79 kJ/mol.

For the substance to freeze, the reverse process occurs. Heat is released from the substance, causing it to transition from the liquid phase to the solid phase. This release of heat results in a decrease in the enthalpy of the system. The magnitude of the enthalpy change for freezing would be the same as the enthalpy change for melting but with an opposite sign. Thus, the enthalpy change for freezing would be ΔH = +79 kJ/mol.

Therefore, the correct answer is (b) ΔH = +79 kJ/mol. It represents the enthalpy change needed for one mole of the substance to freeze. Option B is correct.

For more such question on magnitude. visit :

https://brainly.com/question/30337362

#SPJ8

Answer:

Gas>Liquid>Solid

Explanation:In a gas state, molecules are allowed to move freelyand  rarely collide into nearby particles. In a liquid state, the molecules are contained within the liquid and occasionally bump into each other. now in a solid state the atoms arrange themselves into a structure that the atoms sit very tightly next to each other, sometimes vibarating

Answer:

Actinides

Explanation:

They are defined as "any of the series of fifteen metallic elements from actinium (atomic number 89) to lawrencium (atomic number 103) in the periodic table. They are all radioactive, the heavier members being extremely unstable and not of natural occurrence"

Answer:

Actinides

Explanation:

Actinides are radioactive and human-made elements.

Answer:

Well,

3

×

N

A

oxygen atoms..

Explanation:

Where

N

A

≡

Avogadro's number

≡

6.022

×

10

23

⋅

m

o

l

−

1

.

And so if wl1

oxygen atoms...

i.e.

18.066×

1023

⋅

oxygen atoms..

The statement "Global CO2 concentrations have increased by approximately 1,000 ppm from the year 1800 to today" is False.

In 1800, the global CO2 concentration was around 280 parts per million (ppm). As of today, the concentration has risen to over 410 ppm. This is an increase of approximately 130 ppm, not 1,000 ppm as stated in the question. The increase in CO2 concentrations is primarily due to human activities such as the burning of fossil fuels, deforestation, and industrial processes. This increase has been linked to global climate change and various environmental issues.

To summarize, the statement is false because the increase in global CO2 concentrations from 1800 to today is approximately 130 ppm, not 1,000 ppm.

For more such questions on Global CO2

https://brainly.com/question/14275614

#SPJ11

There are 0,419 moles of glucose in a sample that weights 75.5g.

To calculate the amount in moles of glucose in 75.5g, we first need the molar mass of this compound. To calculate that I'll be using the following atomic mass values:

C: 12

H: 1

O: 16

To calculate the molar mass, we multiply the number of atoms by the respective atomic mass:

(6 * 12) + (12 * 1) + (6 * 16) = 180 g/mol

Since the molar mass is 180 g/mol, we know that each mol has 180 g of glucose:

1 mol glucose ---------- 180g glucose

x --------------------------- 75.5g glucose

Solving for x, we have x = 0.419 moles of glucose

For the solubility of a gas is 0.890 g/L at a pressure of 120 kPa, the solubility of the gas, if the pressure is changed to 100 kPa is mathematically given as

c=0.741g/l

Generally, the equation for the Pressure   is mathematically given as

p=kc

Therefore

k=p/c

k = 120 /0.890

k=134.8

In conclusion, if p=100kpa

c=p/k

c=100/134.8

c=0.741g/l

Read more about mass

https://brainly.com/question/15959704

Answer:

Explanation: It’s the correct answer on Edmentum.

The ideal gas law, which relates the pressure, volume, temperature, and number of moles of an ideal gas, can be applied to real-world situations. By considering a specific scenario and applying the ideal gas law, we can analyze the behavior of gases and make predictions about their properties.

Let's consider a situation where a scuba diver is exploring underwater at a depth of 30 meters. We can apply the ideal gas law, specifically the form known as Boyle's law, which states that the pressure and volume of a gas are inversely proportional at constant temperature.

Question: How does the pressure of the gas in the scuba tank change as the diver descends to a depth of 30 meters, assuming the temperature remains constant?

To answer this question, we can use the ideal gas law equation PV = nRT, where P is the pressure, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature. By keeping the temperature constant, we can observe the relationship between pressure and volume as the diver descends and calculate the change in pressure based on the change in volume.

To learn more about Boyle's law click here:

brainly.com/question/30367133

#SPJ11

Answer:

28 g CO

Explanation:

First convert grams to moles.

1 mole C = 12.011 g (I'm just going to round to 12 for the sake of this problem)

12 g C • \(\frac{1 mol C}{12 g C}\) = 1 mol C

1 mol O = 15.996 g (I'm just going to round to 16)

16 g O • \(\frac{1 mol O}{16 g O}\) = 1 mol O

So the unbalanced equation is:

\(C + O_{2}\) -> \(CO\) (the oxygen has a 2 subscript because it is part of HONClBrIF meaning when not in a compound these elements appear in pairs - called diatomic elements)

The balanced equation is:

\(2 C + O_2\) -> \(2 CO\)

However, carbon is the limiting reactant in this equation and two moles cannot react because only 12 g (1 mole) are present. Therefore, use the equation

\(C + \frac{1}{2} O_2\) -> \(CO\).

1 mole of CO is formed, therefore 12 g + 16 g = 28 g CO.

Answer:

\( \huge{ \boxed{0.779 \: \text{moles}}}\)

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula;

\( \bold{n = \frac{N}{L} \\ }\)

where

From the question

N = 4.69 × 10²³ glucose molecules

\(n = \frac{4.69 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{4.69}{6.02} \\ = 0.77907\)

We have the final answer as

Answer:

Because they usually are eager to give electron so number of electrons will decrease and number of protons will increase and net charge of the element will be positive and will form positive ions

Explanation:

above

According to the electronic configuration, metal atoms tend to loose electrons to form cations and form electropositive elements.

Electronic configuration is defined as the distribution of electrons which are present in an atom or molecule in atomic or molecular orbitals.It describes how each electron moves independently in an orbital.

Knowledge of electronic configuration is necessary for understanding the structure of periodic table.It helps in understanding the chemical properties of elements.

Elements undergo chemical reactions in order to achieve stability. Main group elements obey the octet rule in their electronic configuration while the transition elements follow the 18 electron rule. Noble elements have valence shell complete in ground state and hence are said to be stable.

Learn more about electronic configuration,here:

https://brainly.com/question/13497372

#SPJ2

Answer:

A.kinetic energy doubles as well

B. speed will increase by 1.414 times

Explanation:

kinetic energy is directly proportional to the temperature so doubling the temperature doubles the kinetic energy as well

Answer:

A synthesis reaction occurs when two or more reactants combine to form a single product in a double replacement reaction two compounds exchange elements. Combustion reaction occurs when a substance reacts quickly with oxygen combustion is commonly called burning. Example'- for synthesis reaction is iron+ oxygen —≥ water . Example:- for combustion reaction is often gaseous products.

may be this was ur answer I hope it might help u

Answer:

The main products are ATP, carbon dioxide, and water.

Answer:

\(\huge\boxed{\sf v = 0.017 \ L}\)

Explanation:

Given Data:

Mass = m = 0.08 g

Molar mass of C₂H₂F₄ = (12×2) + (1×2) + (19×4)

= 24 + 2 + 76 = 102 g/mol

Pressure = P = 1.14 atm

Temperature = T = 19.1 °C + 273 = 292.1 K

Gas Constant = R = 0.08206 L atm K⁻¹ mol⁻¹

Required:

Volume = v = ?

Formula:

Pv = nRT

Solution:

Firstly, finding moles (n)

\(\displaystyle n = \frac{mass}{molar \ mass} \\\\n = \frac{0.08 }{102} \\\\n =0.0008 \ mol\)

Now, Finding volume (v)

Rearranging formula

\(\displaystyle v = \frac{nRT}{P} \\\\v = \frac{(0.0008)(0.08206)(292.1)}{1.14} \\\\v = \frac{0.019}{1.14} \\\\v = 0.017 \ L\\\\\rule[225]{225}{2}\)

Answer:

2.38 g of oxygen (O2).

Explanation:

What is given?

Mass of potassium chlorate (KClO3) = 6.06 g.

Molar mass of KClO3 = 122.4 g/mol.

Molar mass of oxygen (O2) = 32 g/mol.

Step-by-step solution:

First, let's state the balanced chemical equation. Remember that the decomposition of a compound produces two or more products:

Now, let's convert 6.06 g of KClO3 to moles using its molar mass:

You can see in the chemical equation that 2 moles of KClO3 produce 3 moles of O2. By doing a rule of three with this data, we obtain that:

The final step is to convert from 0.0743 moles of O2 to grams using its molar mass, like this:

The answer is that we will produce 2.38 g of oxygen (O2) from the decomposition of 6.06 g of potassium chlorate (KClO3).

Answer: PNS, CNS is

Periferal nervous system. Central nervous system.

Explanation:

When 11.2 grams of ethane (g) react with excess oxygen (g), 805.3 kJ of energy is liberated.

What is the meaning of energy?

Energy is defined as the ability to work or cause a change. When a substance is broken down, energy is released or absorbed. Enthalpy is used to represent the amount of energy that a substance contains or releases during a reaction.

Ethane and Oxygen react to form Carbon dioxide and Water.

Determining the energy released during the reaction:

The given balanced equation for this reaction is:

2C2H6(g) + 7O2(g) → 4CO2(g) + 6H2O(g)

Here, the energy change is expressed as ΔHc° = -1560 KJ mol⁻¹Step-by-step explanation for the given problem:Given: 11.2 grams of ethane(g) reacts with excess oxygen(g)

It is given that the energy change when 2 moles of C2H6 react with 7 moles of O2, ΔHc° = -1560. KJ mol⁻¹

So, the energy liberated when 1 mole of C2H6 reacts with 7/2 moles of O2 will be equal to:ΔHc° = -1560 / 2 = -780. KJ mol⁻¹The given mass of ethane is 11.2 g.

Molar mass of ethane = 2 × 12.01 + 6 × 1.01 = 30.07 g/mol

The moles of ethane that will react is given by:

n = mass / molar mass

n = 11.2 / 30.07 = 0.372 mol

As per the balanced equation, 2 moles of C2H6 react with 7 moles of O2.

So, the moles of O2 required to react with 0.372 moles of C2H6 will be equal to:mol of O2 required = 7/2 × n = 7/2 × 0.372 = 1.297 mol

So, we can conclude that when 11.2 grams of ethane(g) react with excess oxygen(g), -805.3 kj of energy is liberated.

To know more about Oxygen, visit:

https://brainly.com/question/27215226

#SPJ11

A solution is a homogenous mixture of two or more pure substances whose composition can vary within certain limits. A solution generally consists of two components, they are called solute and solvent.

A solution is called the supersaturated one which contains more dissolved solute than required for preparing the saturated solution and it is generally prepared by heating the saturated solution, adding more solute and then cooling it gently.

A supersaturated solution is unstable. Adding a small amount of the solute, a seed crystal will cause excess solute to rapidly precipitate or crystallize.

To know more about supersaturated solution, visit;

https://brainly.com/question/16817894

#SPJ1

Answer:

Electronegativity refers to the ability of an atom to attract shared electrons in a covalent bond. The higher the value of the electronegativity, the more strongly that element attracts the shared electrons. ... Thus, fluorine is the most electronegative element, while francium is one of the least electronegative.

Explanation:

If 4 grams of hydrogen with excess oxygen make 18 grams of water, what is the yield in percentage terms? 2H^2 + O^2 —-> 2H^2O

Hydrogen is a gas at standard conditions of temperature and pressure, but around -423 degrees Fahrenheit, it condenses into a liquid (minus 253 degrees Celsius).

The majority of stars and the sun include it, and the planet Jupiter is primarily made of it. Water has the most hydrogen on Earth. All that can be discovered of it as a gas in the air is less than 1 part per million by volume.

To know more about hydrogen visit:

https://brainly.com/question/16979348

#SPJ1

\(\qquad \qquad\huge \underline{\boxed{\sf Answer}}\)

1. As you increase speed is there an increase or decrease in Kinetic Energy?

\(\qquad \sf  \dashrightarrow \: increase\)

2. As you increase mass is there an increase or decrease in Kinetic Energy?

\(\qquad \sf  \dashrightarrow \: increase\)

3. As you decrease speed is there an increase or decrease in Kinetic Energy?

\(\qquad \sf  \dashrightarrow \: decrease\)

4. As you decrease mass is there an increase or decrease in Kinetic Energy?

\(\qquad \sf  \dashrightarrow \: decrease\)