Answer:
1 mole of platinum
Explanation:
To obtain the number of mole(s) of platinum present, we need to determine the empirical formula for the compound.
The empirical formula for the compound can be obtained as follow:
Platinum (Pt) = 117.4 g
Carbon (C) = 28.91 g
Nitrogen (N) = 33.71 g
Divide by their molar mass
Pt = 117.4 / 195 = 0.602
C = 28.91 / 12 = 2.409
N = 33.71 / 14 = 2.408
Divide by the smallest
Pt = 0.602 / 0.602 = 1
C = 2.409 / 0.602 = 4
N = 2.408 / 0.602 = 4
The empirical formula for the compound is PtC₄N₄ => Pt(CN)₄
From the formula of the compound (i.e Pt(CN)₄), we can see clearly that the compound contains 1 mole of platinum.
Given :
Number of molecules of
.
To Find :
How many moles are in given number of molecules.
Solution :
We know, in 1 moles of any element/compound contains
at atoms/molecules.
So, number of moles in
molecules are :

Therefore, number of moles are 8.97 .
Answer:

Explanation:
We are asked to find how much heat a sample of copper absorbs when the temperature is increased.
Since we know the mass, temperature increase, and specific heat capacity, we can use the following formula to calculate heat.

The mass of the copper sample is 100 grams, the temperature is changed or increased by 30.0 degrees Celsius, and the specific heat of copper is 0.39 Joules per gram degrees Celsius.
- m= 100 g
- c= 0.39 J/g °C
- ΔT= 30.0 °C
Substitute the values into the formula.

Multiply the first two values. Note that the units of grams cancel.

Multiply again, this time the units of degrees Celsius cancel.

The copper sample absorbs <u>1170 Joules</u> of heat and <u>Choice B </u>is correct.
Answer:
A polar molecule has both a partial positive and a partial negative. Since NaCl (sodium chloride) is made out of Na+ and Cl- ions, the positive and negative parts of the water will pull on these ions individually since positive attracts negative and negative attracts positive. This magnetic force causes the Na+ and the Cl- ions to be pulled apart.
Explanation:
Answer:10^27 atoms in an apple
Explanation: