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2 years ago

Dmitri mendeleev contribution to the periodic table.

1 answer:

8 0

In 1871, a Russian Chemist, Dimitri Mendeleev, gave a useful scheme for classification of elements. He presented the first regular periodic table in which elements of similar chemical properties were arranged in eight vertical columns called groups. The horizontal rows of table were called periods. He arranged elements in ascending order of their atomic masses and found that elements having similar chemical properties appeared at regular intervals. This observation was called Periodic Law.

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Which process transfers heat from the ground to the air touching it? Conduction Convection Evaporation Radiation

Delicious77 [7]

Convection

Explanation:

Heat is a form of thermal energy borne as result of thermal energy. It is observed as temperature differences between places.

There are different types of heat transfer:

Conduction
Convection
Radiation

Conduction is a heat transfer which involves the actual movement of the collision of the molecules of the medium.

Convection is a heat transfer in fluids by their movement from areas of higher to places of lower heat.

Radiation is heat transfer using electromagnetism and does not involve molecules of the medium

The process of heat transfer from ground to the air touching it is convection. It involves particles of the air.

Learn more:

Convection brainly.com/question/1140127

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8 0

3 years ago

Why would the federal government and city government find it necessary regulate water standard?

Helga [31]

They do this so that when you drink it or use it the contaminates that used to be in it dont make you sick

4 0

3 years ago

What does group 16 (oxygen family) have in common

Dimas [21]

Answer: here is your answer

Explanation:

The oxygen family consists of the elements that make up group 16 on the periodic table: oxygen, sulfur, selenium, tellurium, and polonium. These elements all have six electrons in their outermost energy level, accounting for some common chemical properties among them.

7 0

3 years ago

Read 2 more answers

A very hot cube of copper metal (32.5 g) is submerged into 105.3 g of water at 15.4 0C and it reach a thermal equilibrium of 17.

zysi [14]

Answer:

The initial temperature of the metal is 84.149 °C.

Explanation:

The heat lost by the metal will be equivalent to the heat gain by the water.

- (msΔT)metal = (msΔT)water

-32.5 grams × 0.365 J/g°C × ΔT = 105.3 grams × 4.18 J/g °C × (17.3 -15.4)°C

-ΔT = 836.29/12.51 °C

-ΔT = 66.89 °C

-(T final - T initial) = 66.89 °C

T initial = 66.89 °C + T final

T initial = 66.89 °C + 17.3 °C

T initial = 84.149 °C.

7 0

3 years ago

How many grams of O₂ can be prepared from the thermal decomposition of 4.27 kg of HgO? Name and calculate the mass (in kg) of th

babymother [125]

Mass of Oxygen is: 0.784gm

Potassium chlorate is KClO3 and the decomposition looks like this...

2KClO3 ==> 2KCl + 3O2

4.50 g KClO3 x 1 mole/122.55 g = 0.0367 moles

0.0367 moles KClO3 x 3 moles O2/2 moles KClO3 = 0.0245 moles O2 (see mole ratio in balanced equation)

mass of O2 = 0.0245 moles O2 x 32 g/mole = 0.784 g O2 formed

<h3>What is the pressure of a mixture of CO2 and KR?</h3>

A mixture of CO2 and Kr weighs 37.0 g and exerts a pressure of 0.737 atm in its container. is expensive, you wish to recover it from the mixture.

<h3>How much oxygen is created when one mole of potassium chlorate breaks down?</h3>

in the reaction 2K C lO3 2K C l + 3O2 K C lO3? This demonstrates that 3 moles of oxygen gas are created for every 2 moles of degraded potassium chlorate.

<h3>How is high pressure liquid CO2 produced?</h3>

High pressure liquid CO 2 is produced by compressing the gaseous CO 2 in multistage compressors to pressures in the neighbourhood of 69 bar (1000,76 psi) pressure, then cooling it to around 18 °C (64,4 °F). It is customarily filled into specially constructed steel cylinders.

Learn more about decomposition HgO:

brainly.com/question/15066243

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5 0

2 years ago