How many elements are there in world​

(NH₄)₂S

%N=  41.18%

%H =11.76%

%S=47.06%

Mg(NO₃)₂

%Mg=32.43%

%N=18.92%

%O=(64.86%

Given

(NH₄)₂S

Mg(NO₃)₂

Required

The percent composition

Solution

(NH₄)₂S MW=68 g/mol

%N=2. Ar N  / MW (NH₄)₂S x 100%

%N= (2.14/68) x 100% = 41.18%

%H =(8.1/68) x 100%=11.76%

%S=(32/68)x 100%=47.06%

Mg(NO₃)₂ MW=148 g/mol

%Mg=(2.24/148)x100%=32.43%

%N=(2.14/148)x100%=18.92%

%O=(6.16/148)x100%=64.86%

Answer:

When one object is rubbed against another, static electricity can be created. This is because the rubbing creates a negative charge that is carried by electrons. The electrons can build up to produce static electricity. For example, when you shuffle your feet across a carpet, you are creating many surface contacts between your feet and the carpet, allowing electrons to transfer to you, thereby building up a static charge on your skin. When you touch another person or an object, you can suddenly discharge the static as an electrical shock.

Similarly, when you rub a balloon on your head it causes opposite static charges to build up both on your hair and the balloon. Consequently, when you pull the balloon slowly away from your head, you can see these two opposite static charges attracting one another and making your hair stand up.

Materials

• Balloon

• An object made out of wool (such as a sweater, scarf, blanket or ball of yarn)

• Stopwatch

• A wall

• A partner (optional)

Preparation

• Blow up the balloon and tie off the end.

• Have your partner prepare to use the stopwatch.

Procedure

• Hold the balloon in a way that your hand covers as little of its surface area as possible, such as by using only your thumb and pointer finger or by gripping the balloon by its neck where it is tied off.

• Rub the balloon on the woolly object once, in one direction.

• Hold the balloon up on the wall with the side that was rubbed against the wool facing the wall, then release it. Does the balloon stay stuck on the wall? If the balloon stays stuck, have your partner immediately start the stopwatch to time how long the balloon remains bound to the wall. If the balloon does not stick, move to the next step.

• Touch the balloon to a metal object. Why do you think this is important to do?

• Repeat the above process but each time increase the number of times you rub the balloon on the woolly object. Rub the balloon in the same direction each time. (Do not rub the balloon back and forth.)

Observations and results

In general, did the balloon stick to the wall for a longer amount of time as you increased the number of times you rubbed the balloon on the woolly object?

Wool is a conductive material, which means it readily gives away its electrons. Consequently, when you rub a balloon on wool, this causes the electrons to move from the wool to the balloon's surface. The rubbed part of the balloon now has a negative charge. Objects made of rubber, such as the balloon, are electrical insulators, meaning that they resist electric charges flowing through them. This is why only part of the balloon may have a negative charge (where the wool rubbed it) and the rest may remain neutral.

When the balloon has been rubbed enough times to gain a sufficient negative charge, it will be attracted to the wall. Although the wall should normally have a neutral charge, the charges within it can rearrange so that a positively charged area attracts the negatively charged balloon. Because the wall is also an electrical insulator, the charge is not immediately discharged. However, because metal is an electrical conductor, when you rub the balloon against metal the extra electrons in the balloon quickly leave the balloon and move into the metal so the balloon is no longer attracted and does not adhere.

HOPE IT HELPS

PLEASE MARK ME BRAINLIEST

The test variables and the control variable and the outcome variables are Balloons, the electrical insulators, and resist electric charges flowing through them.

When we brush a balloon against our head, the hair and balloon both develop opposing static charges. We can see how these two opposing static charges attract one another and make our hair stand up as the balloon is gently dragged away from our head.

When a balloon is rubbed to the wall, it will be attracted to the wall. Because the wall is an electrical insulator, the charge is not quickly discharged.

The excess electrons in the balloon immediately leave the balloon and go into the metal when it is rubbed against metal. As a result, the balloon is no longer attracted to the metal and does not adhere.

Therefore, Balloons, which act as electrical insulators and prevent the flow of electric charges, serve as the test, control, and outcome variables.

To learn more about variables, refer to the link:

https://brainly.com/question/29736640

#SPJ2

Answer:When acids react with carbonates,---CO2--------gas is liberated.

Explanation:

Acids liberate Carbon IV oxide when they react with  Carbonates  bicarbonate

For examples

Acid +carbonate  ⟶ Salt + Water + Carbon dioxide

Calcium carbonate + Hydrochloric acid  will give Calcium chloride with the liberation of CO2 gas and water

CaCO3 + 2HCl →CaCl2 + CO2 + H2O

To Test for the presence of the CO2 Liberated, we pass the gas through lime water, if the lime water turns milky, then C02 gas is confirmed.

Answer:Actinide Group

Explanation:Plutonium is a member of the actinide group in the periodic table. Plutonium atoms have 94 electrons and 94 protons with 2 valence electrons in the outer shell. There are 150 neutrons in the most abundant isotope.

Answer:

2KOH + 3co2 ------->2ксоз + 2Н20

x CO₂  = 0.236

x H₂  = 0.764

Given

P CO₂ = 217 mmHg

P H₂ = 703 mmHg

Required

The mole fraction

Solution

Dalton's law :

The total pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases  

Can be formulated:  

P tot = P1 + P2 + P3 ....  

P tot for the mixture :

= 217 mmHg + 703 mmHg

= 920 mmHg

Mole fraction of each gas :

x CO₂ = 217 mmHg/920 mmHg = 0.236

x H₂ = 703 mmHg/920 mmHg = 0.764

Answer:

This strong current of warm water influences the climate of the east coast of Florida, keeping temperatures there warmer in the winter and cooler in the summer than the other southeastern states. Since the Gulf Stream also extends toward Europe, it warms western European countries as well.

Answer:

warm climates in northern Europe

Explanation:

I took the test in K12 and this was the answer :)

Answer:

u didnt give a worksheet

Explanation:

Explanation:

V is not an SI base unit. (C)

Volume can be expressed as m³ in units.

In turn, m is the SI base units for length.

Solution :

Given :

length of silver cube = 2.28 cm

length of gold cube = 2.75 cm

Initial temperature = 82.8°C

Volume of silver cube is

Volume [tex]$=(\text{edge length})^3$[/tex]

               =    [tex]$(2.28)^3$[/tex]

                [tex]$= 11.8 \ cm^3$[/tex]

mass of silver cube

Mass, [tex]$m_s = \text{density} \times \text{volume} $[/tex]

                = 10.5 x 11.8

                = 123.9 g

Similarly, the volume of gold cube is

Volume [tex]$=(\text{edge length})^3$[/tex]

               =    [tex]$(2.75)^3$[/tex]

                [tex]$= 20.79 \ cm^3$[/tex]

mass of gold cube

Mass, [tex]$m_g = \text{density} \times \text{volume}$[/tex]

                = 19.3 x 20.79

                = 401.247 g

Now

heat lost by silver and gold cube = heat gained by water

∴[tex]$m_g .c_g \Delta T + m_s .c_s \Delta T = m_w.c_w \Delta T$[/tex]

[tex]$m_g .c_g (82.8- T) + m_s .c_s (82.8- T) = m_w.c_w (T - 20.2)$[/tex]

[tex]$401.247 \times 0.1264 (82.8- T) + 123.9 \times 0.2386 (82.8- T) = 111.5 \times 4.184 (T - 20.2)$[/tex]

Now solving the equation

[tex]$50.71 (82.8- T) + 29.56 (82.8- T) = 466.51 (T - 20.2)$[/tex]

Final temperature, T = 31.27°C

Answer:

The molar concentration of water sample that has 1 ppm arsenic is 1.33  * 10⁻⁵ M

Explanation:

1 parts per million (ppm) means 1 part of solute in a million parts of solution.

Since 1 million, 10⁶ mg = 1 kg, 1 ppm = 1 mg/kg

The density of water = 1.0 kg/L, therefore, the volume of 1 kg of water = 1 L

Hence, 1 ppm = 1 mg/kg = 1 mg/L

molar mass of arsenic = 75 g/mol

1 mg of arsenic = 10⁻³ g or 0.001 g

number of moles of arsenic in 0.001 g of arsenic = 0.001 g / 75 g/mol = 1.33  * 10⁻⁵ moles

Molar concentration = 1.33 * 10⁻⁵ mol / 1 L = 1.33  * 10⁻⁵ M

Therefore, the molar concentration of water sample that has 1 ppm arsenic is 1.33  * 10⁻⁵ M

A scientist exploring evidence from other fields of science to support findings is an example of a scientist using creativity.

Creativity is a mental cognitive ability that involves the creation and/or discovery of a hidden process.

In science, creativity refers to the application of mental skills to create new experimental designs and extrapolate findings.

In conclusion, a scientist exploring evidence from other fields of science to support findings is an example of a scientist using creativity.

Learn more about creativity here:

https://brainly.com/question/26061350

#SPJ1

Answer:

Heated water begins circulating in a fish tank.

Explanation:

Answer:

Heated water begins circulating in a fish tank.

Answer:

I think A does because there are so many letters in their so a

Answer: Inorganic chemistry

Explanation:

Inorganic chemistry can be defined as the branch of chemistry which studies the behavior of the inorganic compounds. Inorganic compounds are those compounds which lack carbon hydrogen bonding. The carbon monoxide, carbon dioxide, sodium chloride and water are the examples of inorganic compounds. This branch also studies the effect of these chemical compounds on the living things. The water and salts are chemicals which regulate the chemical and physiological reactions in the body.

Answer:

33.6 i think

Explanation:

Answer:

5 g of H₂ are contained in the vessel

Explanation:

A typical excersise of conversion:

We determine molar mass of H₂.

This is a dyatomic molecule, as molar mass of H is 1g/mol, molar mass of H₂ will be 2g/mol.

Let's make the conversion of units:

2.5 mol . 2g/mol = 5 g

5 g of H₂ are contained in the vessel

Mass of hydrogen in the vessel = 5 grams

The number of moles is defined as the given mass over molar mass.

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]

Given:

Number of moles= 2.5 mol

To find:

Mass of hydrogen=?

Molar mass of hydrogen =2g/mol

On substituting the values in the given formula we will get:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}\\\\\text{Given mass}=\text{Number of moles}*\text{Molar mass}\\\\\text{Given mass}=2.5 mol* 2g/mol\\\\\text{Given mass}=5 g[/tex]

Thus, mass of hydrogen in the vessel is 5 grams.

Learn more:

brainly.com/question/14464650

Answer:

The driver in the car because a truck is a bigger vehicle and the impact of a truck to a car is more damaging than a car to a truck. Weight difference is the key I think.

Explanation:

Answer: Positive

Explanation: Just a guess

Answer:

Positive

Explanation:

Answer: with dog figs- it is 590

With decimals it is 589.68

Explanation:

Answer:

A.) an exothermic reaction that has an increase in disorder.

Explanation:

got it correct (unit review test)

Answer:

Atoms

Explanation:

Answer:

2 Al(s) + 3 H₂SO₄(aq) ⇒ Al₂(SO₄)₃(aq) + 3 H₂(g)

Explanation:

Let's consider the unbalanced equation for the single replacement reaction between Al and H₂SO₄.

Al(s) + H₂SO₄(aq) ⇒ Al₂(SO₄)₃(aq) + H₂(g)

We will begin balancing S atoms by multiplying H₂SO₄ by 3.

Al(s) + 3 H₂SO₄(aq) ⇒ Al₂(SO₄)₃(aq) + H₂(g)

Then, we balance Al atoms by multiplying Al by 2.

2 Al(s) + 3 H₂SO₄(aq) ⇒ Al₂(SO₄)₃(aq) + H₂(g)

Finally, we get the balanced equation by multiplying H₂ by 3.

2 Al(s) + 3 H₂SO₄(aq) ⇒ Al₂(SO₄)₃(aq) + 3 H₂(g)

1.63 M

Math

Pre-Algebra

Order of Operations: BPEMDAS

Equality Properties

Chemistry

Unit 0

Aqueous Solutions

Step 1: Define

1.43 mol NaCl (sodium chloride)

0.875 L solution

Step 2: Find M

Step 3: Check

Follow sig fig rules and round. We are given 3 sig figs.

1.63429 M ≈ 1.63 M

Answer:

The frequency of coral diseases has increased significantly over the last 10 years, causing widespread mortality among reef-building corals. Many scientists believe the increase is related to deteriorating water quality associated with human-made pollutants and increased sea surface temperatures.

Explanation:

Answer:

sullage or grey water

Explanation:

sources include: sinks, showers, baths, washing machines, dishwashers and no not toliets.

Answer:

Yellow fruit and dwarf vines are recessive traits in tomatoes. Red fruit and tall vines are dominant. Complete a Punnett square and answer the questions for a completely dominant red and tall plant crossed with a heterozygous red and dwarf plant.

Explanation:

Answer: A

Explanation:

Answer:

C

Explanation:

because the combustion reaction produce vapor water and CO2