Answer:
Mass of 1 mole of copper is 63.83 g.
0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
Explanation:
Mass of 1 copper atom,m = 

Mass of 1 mole of copper :
= 
Mass of 1 mole of copper = 63.83 g
Mass of copper penny = 2.5 g
Atomic mass of copper = 63.83 g/mol
Moles of copper in 2.5 g of copper penny:

0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
1) Conversion of an isotope one chemical element or an isotope into another chemical element is called as nuclear transmutation.
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2) In a nuclear transmutation reactions</span> can be achieved either due to radioactive decay or due to nuclear reactions.
3) In this technique, it is possible to convert a stable element into radioactive atom by bombarding in with high speed particles. The initial stable nuclei is referred as parent nuclei, the fast moving particle is referred as projectile while new element which is formed is called as daughter element.
4) In the present reaction:
<span>1 1 H+ 1 0 n -> 2 1 H
1 1H is a parent nuclei which is bombarded with the fast moving projectile
(1 0 n) to generate a new daughter nuclei (2 1H). </span>
Answer:

Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary for us to set the equation for the calculation of density and mass divided by volume:

Thus, we can find the mass of the unknown by subtracting the total mass of the liquid to the mass of the flask and the liquid:

So that we are now able to calculate the density in g/mL first:

Now, we proceed to the conversion to lb/in³ by using the following setup:

Regards!
Answer: both compounds have ionic bond between metal and non-metal
Explanation: both Sr and Mg are earth alkaline metals and form ions Mg^2+
And Sr^2+. Br forms ion Br^- and S ion is S^2+.