Answer:
the chemical element of atomic number 2, an inert gas which is the lightest member of the noble gas series.
Explanation:
Because it is very unreactive, helium is used to provide an inert protective atmosphere for making fibre optics and semiconductors, and for arc welding. Helium is also used to detect leaks, such as in car air-conditioning systems, and because it diffuses quickly it is used to inflate car airbags after impact.
Well countries near the quitter of warmer than countries than the poles. So the mystery island would probably be near the equator near Florida or in Florida
Answer:
4.4 g
Explanation:
Step 1: Write the balanced equation
Cu + 4 HNO₃ ⇒ Cu(NO₃)₂ + 2 NO₂ + 2 H₂O
Step 2: Calculate the moles corresponding to 3.2 L of NO₂ at STP
At standard temperature and pressure, 1 mole of NO₂ occupies 22.4 L.
3.2 L × 1 mol/22.4 L = 0.14 mol
Step 3: Calculate the moles of Cu needed to produce 0.14 moles of NO₂
The molar ratio of Cu to NO₂ is 1:2. The moles of Cu needed are 1/2 × 0.14 mol = 0.070 mol.
Step 4: Calculate the mass corresponding to 0.070 moles of Cu
The molar mass of Cu is 63.55 g/mol.
0.070 mol × 63.55 g/mol = 4.4 g
The given reaction Mg + O₂ → MgO is a type of Synthesis reaction. Hence option (1) is correct.
<h3>What is Synthesis reaction ?</h3>
Synthesis reactions are reactions that occur when two different atoms or molecules interact to form one molecule or compound.
It is also known as combination reaction
In the given reaction Mg and O combines with each other to form one product i.e, MgO. Hence, The given reaction Mg + O₂ → MgO is a type of Synthesis reaction. Thus, option (1) is correct.
Learn more about chemical reaction here ;
brainly.com/question/27948961
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