Answer:
9.00
Explanation:
Data:
[H⁺] = 1.0 × 10⁻⁹ mol·L⁻¹
Calculation:
pH = -log[H⁺] = -log(1.0 × 10⁻⁹) = -log(1.0) - log(10⁻⁹) = -0.00 - (-9) = -0.00 + 9 = 9.00
Answer:
Highest energy will be equal to 
Explanation:
Charged on doubly ionized helium atom 
It is accelerated with maximum voltage of 3 MV
So voltage 
Now energy is given by 
So highest energy will be equal to 
Covalent network. <span>A solid that is extremely hard, that has a very high melting point, and that will not conduct electricity either as a solid or when molten is held together by a continuous three-dimensional network of covalent bonds. Examples include diamond, quartz (SiO </span><span>2 </span>), and silicon carbide (SiC). The electrons are constrained in pairs to a region on a line between the centers of pairs of atoms.<span>
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The reaction between Na2S and CuSO4 will give us the balanced chemical reaction of,
Na2S + CUSO4 --> Na2SO4 + CuS
This means that for every 78g of Na2S, there needs to be 159.6 g of CuSO4. The ratio is equal to 0.4887 of Na2S: 1 of CuSO4. Thus, for every 12.1g of CuSO4, we need only 5.91 g of Na2S. Thus, there is an excess of 9.58 g of Na2S. The answer is letter C.