Hai :3
Do you know how to find valence electrons? The amount of valence electrons that an element has depends on its group number, with an exception towards transitional elements.
For example, Oxygen is in group 16, which makes it have 6 valence electrons. Group 1 has 1, group 2 has 2, group 13 has 3, group 14 has 4, and so on.
What about transitional elements? The elements ranging from group 3 until 11 have different valence electrons because (advanced) if you look at their electron configuration, they have d orbital electrons (they can be edited), which gives them a varied valence configuration.
1. Iodine: Group 17 - 7 valence electrons Calcium: Group 2 - 2 valence electrons Chlorine: Group 17 - 7 valence electrons Sodium - Group 1 - 1 valence electron Neon - Group 18 - 8 valence electrons Copper - Group 11 - *Copper is a transitional element!* Those within group 11 usually have either 1 or 2 electrons. Your teacher did not specify which copper he's asking, so you could say that there is Copper (I), which has 1 valence electron, and also Copper (II), which has 2 valence electrons.
Moving to your second question, to see how many electron shells an element has, you look at where they are in their period (horizontal row)
For example, oxygen is in period 2, therefore, it has two electron shells. Period 1 has 1, period 2 has 2, period 3 has 3, and so on.
1. 1. Iodine: Period 5 - 5 electron shells Calcium: Period 4 - 4 electron shells Chlorine: Period 3 - 3 electron shells Sodium - Period 3- 1 electron shells Neon - Period 2 - 2 electron shells Copper - Period 4 - 4 electron shells
Answer:
Do you know how to find valence electrons? The amount of valence electrons that an element has depends on its group number, with an exception towards transitional elements.
For example, Oxygen is in group 16, which makes it have 6 valence electrons. Group 1 has 1, group 2 has 2, group 13 has 3, group 14 has 4, and so on.
What about transitional elements? The elements ranging from group 3 until 11 have different valence electrons because (advanced) if you look at their electron configuration, they have d orbital electrons (they can be edited), which gives them a varied valence configuration.
1. Iodine: Group 17 - 7 valence electrons Calcium: Group 2 - 2 valence electrons Chlorine: Group 17 - 7 valence electrons Sodium - Group 1 - 1 valence electron Neon - Group 18 - 8 valence electrons Copper - Group 11 - *Copper is a transitional element!* Those within group 11 usually have either 1 or 2 electrons. Your teacher did not specify which copper he's asking, so you could say that there is Copper (I), which has 1 valence electron, and also Copper (II), which has 2 valence electrons.
Moving to your second question, to see how many electron shells an element has, you look at where they are in their period (horizontal row)
For example, oxygen is in period 2, therefore, it has two electron shells. Period 1 has 1, period 2 has 2, period 3 has 3, and so on.
1. 1. Iodine: Period 5 - 5 electron shells Calcium: Period 4 - 4 electron shells Chlorine: Period 3 - 3 electron shells Sodium - Period 3- 1 electron shells Neon - Period 2 - 2 electron shells Copper - Period 4 - 4 electron shells
Explanation:
2)An internal combustion engine doesn't have a cylinder and a piston.
3)The burning of fuel occurs inside the cylinder with the piston in an internal combustion engine.
4)An external combustion engine doesn't have a cylinder and a piston
Answer: The correct answer is option (3).
Explanation:
Internal combustion engine: An engine which generates motive power by burning the fuel with air inside the engine. Heat produced is used to move piston or to perform other work as they expand.
External combustion engine : An engine where motive power is generated by providing the heat to the fluid present inside the engine from the external source. Here combustion of the fuel is not inside the engine.
Hence,the correct answer is option (3).
The answer is 3) The burning of fuel occurs inside the cylinder with the piston in an internal combustion engine.
Explanation: I took the test :)
Answer:
Usually lung cancer.
Explanation:
It causes cells in your lungs to be damaged, which can lead to lung cancer.
Usual symptoms include
persistent cough
coughing up blood
wheezing
shortness of breath
hoarseness
chest pain, especially when you cough or laugh
frequent infections such as bronchitis and pneumonia
Radon is part of the environment and generally isn’t harmful. But long-term exposure to high levels of radon can put you at risk of developing lung cancer, especially if you smoke
Answer:
Liquefied petroleum gas
Answer:
Liquefied petroleum gas or liquid petroleum gas(LPG or LP gas),
Answer:
Option(b)
Finding new sources of fresh water is not the correct method For solving the world water crisis the solution
Explanation:
Very small amount of water available on earth is freshwater and can be used by humans for drinking and other basicnecessities. Finding a new source for fresh water is a difficult also there is an no source found yet according to physical geography of the earth
Water consumption is need of the hour as the population of 7 billion can not survive without it and reducing over consumption can help savehugeamounts of water.
Answer:
The correct answer is option b. finding new sources of water
Explanation:
The other options are more proactive ways of alleviating the crisis, while finding new sources of freshwater is hardly an option. That would likely involve melting the glaciers to extract the Earth's largest fresh water reserves, which would subsequently destroy polar ecosystems and alter the thermohaline circulation of water across the globe, which relies heavily on the Earth's polar regions and has a large effect on the planet's climate.