The relative formula mass (M) of XCO, is 84 Relative atomic masses (A.): C = 12 O = 16
Calculate the relative atomic mass (A) of X.

x = 56

relative atomic mass is 58.933

Explanation:

finding the relative molecular mass of x first...

x + (C ×1) + (O ×1) =84

x + (12 ×1) + ( 16 × 1) =84

x + 12 + 16 =84

collect like terms

x = 84-12+16

x= 56

now...

half of 56...

56÷2 =27

and 27 is the atomic number of cobalt...

so relative atomic mass of cobalt is 58.933.

odds are decent that your handwriting right now looks a little bit different than it did five years ago, and will look different again in five more. when i look back through my notebooks from middle school to now, i see a long, slow progression from meticulous and teeny letters to bigger, sloppier ones, plus a few side detours: sometime in high school, for example, i decided those loopy cursive lowercase f’s were just the coolest, adopting them as the lone rep for cursive in my otherwise all-print handwriting.

explanation:

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.