Answer:
0.67 g
Explanation:
We know that 1 mole of an element is 6.02 x 10^(23) atoms
Now, arsenic has 5.49 × 10²¹ atoms
Thus;
Number of moles of arsenic = 5.49 × 10²¹ × 1/6.02 x 10^(23) = 9 × 10^(-3) moles
We are told that;
one mole of arsenic = 74.92 g.
Thus, 9 × 10^(-3) moles = 9 × 10^(-3) × 74.92/1 = 0.67428 g ≈ 0.67 g
Given the following equation: I N2(g) + 3H2(g) → _2_NH3(e) a. ... Calculate the number of grams of NH3 produced by the reaction of 5.40 g of ... C. How many grams of nitrogen are needed to produce 15.3 g of NH3?
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Very sorry if this is wrong!
Let us assume that there is a 100g sample of Opal. The masses of each element will be:
29.2g Si
33.3g O
37.5g H2O
Now we divide each constituent's mass by its Mr to get the moles present
Si: (29.2 / 28) = 1.04
O: (33.3 / 16) = 2.08
H2O: (37.5 / 18) = 2.08
Now we divide by the smallest number and obtain:
Si: 1
O: 2
H2O: 2
Thus, the empirical formula of Opal is:
SiO2 . 2H2O
Answer: ok lets battle XD
Explanation:
Answer:
All of the above.
Explanation:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.
This process is not reversible and a change of energy that is sometimes heat is given off.