The heart is protected from the bones by the rib cage or the thoracic cage. It protects both the heart and the lungs. The rib cage is composed of 12 pair of ribs, the sternum and thoracic vertebrae. All ribs are connected to the thoracic vertebrae. The rib cage also do not only protect the heart and lungs but also support the body and aid in respiratory function.
1) A Car engine.............. Hope it helps, Have a nice day :)
Answer:
Explanation:
M(s) → M (g ) + 20.1 kJ --- ( 1 )
X₂ ( g ) → 2X (g ) + 327.3 kJ ---- ( 2 )
M( s) + 2 X₂(g) → M X₄ (g ) - 98.7 kJ ----- ( 3 )
( 3 ) - 2 x ( 2 ) - ( 1 )
M( s) + 2 X₂(g) - 2 X₂ ( g ) - M(s) → M X₄ (g ) - 98.7 kJ - 2 [ 2X (g ) + 327.3 kJ ] - M (g ) - 20.1 kJ
0 = M X₄ (g ) - 4 X (g ) - M (g ) - 773.4 kJ
4 X (g ) + M (g ) = M X₄ (g ) - 773.4kJ
heat of formation of M X₄ (g ) is - 773.4 kJ
Bond energy of one M - X bond = 773.4 / 4 = 193.4 kJ / mole
The answer is Na-F. The F has highest electronegativity among these elements. So we need to find the element with smallest electronegativity. And this element is Na.
Answer:
3 grams
Explanation:
14 g of N2 is 1/2 mole
If you halve the N2 in the balanced equation , you have to halve the H2 down to 1.5 moles of H2 which is 3 grams
