answer:
The mass of 4×10²¹ atoms Pt is ≈ 1 g Pt.
explanation:
Cacl2 dissolve in water according to the following equation
Cacl2 + H2O = Ca(OH) + Hcl
Volume= moles/molarity
The reacting ratio between CaCl2 to Ca(OH) is 1:1
therefore moles of solution is also 0.0262 moles hence volume is =
0.0262mol/ 0.52mol/l = 0.0504L or50.4ml
Answer A
x-ray optical telescope.
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