Answer:
Chromium, calcium, and osmium
Explanation:
These elements are metals, considering this, these elements electron shells(orbitals) are further away from the nucleus, with this, their attractions are not as strong as non-metals, so some of their electrons are able to move freely.
When you accumulate many atoms, these metals can form a "sea of electrons" because they all have loose electrons interacting with each other. This allows easy conduction of heat and electricity.
The balanced equation for the above reaction is as follows;
2K + Br₂ --> 2KBr
Stoichiometry of Br₂ to KBr is 1:2
we have been told that K is present which means that Br₂ is the limiting reactant. Limiting reactant is the reactant that is fully consumed in the reaction and amount of product formed depends on amount of limiting reactant present.
Number of Br moles reacted - 21.4 g / 160 g/mol = 0.134 mol
According to stoichiometry,
1 mol of Br₂ forms 2 mol of KBr
therefore 0.134 mol of Br₂ forms 2x0.134 = 0.268 mol of KBr
mass of KBr formed - 0.268 mol x 119 g/mol = 31.9 g of KBr
a mass of 31.9 g of KBr is formed
A simple magnetic compass can be used
Answer:
168.812 g/mol
Explanation:
atomic mass. of Be= 9.012
atomic mass of Br= 79.90
because there is a 2 after Br you double the atomic mass
79.90(2)= 159.8
To find the molar mass add the atomic masses of each element
9.012+159.8=168.812
