See the correct answer is b.)PbS
Answer:
Chemistry is a branch of science that involves the study of the composition, structure and properties of matter. Often known as the central science, it is a creative discipline chiefly concerned with atomic and molecular structure and its change, for instance through chemical reactions.Explanation:Chemistry is a branch of science that involves the study of the composition, structure and properties of matter. Often known as the central science, it is a creative discipline chiefly concerned with atomic and molecular structure and its change, for instance through chemical reactions.
Answer:
He will decide which drink is to be served to whom, by the use of litmus paper.
Explanation:
The litmus paper is the most common indicator to determine the acidity or basicity of a solution. Blue litmus paper changes its color to red when a solution changes from basic to acidic while red litmus paper changes its color to blue when the opposite occurs (acid → basic).
First of all the litmus paper strip, pH indicator, is immersed in a solution and allowed to pass between 10 and 15 seconds while keeping the strip submerged. Afterwards it is removed, and then the strip compares the color. If the color is diffuse, there is a color scale where it is determined which solution has alkaline or acidic pH
Answer:
<h3>25.0 grams is the mass of the steel bar.</h3>
Explanation:
Heat gained by steel bar will be equal to heat lost by the water
![Q_1=-Q_2](https://tex.z-dn.net/?f=Q_1%3D-Q_2)
Mass of steel=
Specific heat capacity of steel =
Initial temperature of the steel = ![T_1=2.00^oC](https://tex.z-dn.net/?f=T_1%3D2.00%5EoC)
Final temperature of the steel = ![T_2=T=21.50^oC](https://tex.z-dn.net/?f=T_2%3DT%3D21.50%5EoC)
![Q_1=m_1c_1\times (T-T_1)](https://tex.z-dn.net/?f=Q_1%3Dm_1c_1%5Ctimes%20%28T-T_1%29)
Mass of water= ![m_2= 105 g](https://tex.z-dn.net/?f=m_2%3D%20105%20g)
Specific heat capacity of water=![c_2=4.18 J/g^oC](https://tex.z-dn.net/?f=c_2%3D4.18%20J%2Fg%5EoC)
Initial temperature of the water = ![T_3=22.00^oC](https://tex.z-dn.net/?f=T_3%3D22.00%5EoC)
Final temperature of water = ![T_2=T=21.50^oC](https://tex.z-dn.net/?f=T_2%3DT%3D21.50%5EoC)
![Q_2=m_2c_2\times (T-T_3)-Q_1=Q_2(m_1c_1\times (T-T_1))=-(m_2c_2\times (T-T_3))](https://tex.z-dn.net/?f=Q_2%3Dm_2c_2%5Ctimes%20%28T-T_3%29-Q_1%3DQ_2%28m_1c_1%5Ctimes%20%28T-T_1%29%29%3D-%28m_2c_2%5Ctimes%20%28T-T_3%29%29)
On substituting all values:
![(m_1\times 0.452 J/g^oC\times (21.50^o-2.00^oC))=-(105 g\times 4.18 J/g^oC\times (21.50^o-22.00^o))\\\\m_1*8.7914=241.395\\\\m_1=\frac{219.45}{8.7914} \\\\m_1=24.9\\\\ \approx25 \texttt {grams}](https://tex.z-dn.net/?f=%28m_1%5Ctimes%200.452%20J%2Fg%5EoC%5Ctimes%20%2821.50%5Eo-2.00%5EoC%29%29%3D-%28105%20g%5Ctimes%204.18%20J%2Fg%5EoC%5Ctimes%20%2821.50%5Eo-22.00%5Eo%29%29%5C%5C%5C%5Cm_1%2A8.7914%3D241.395%5C%5C%5C%5Cm_1%3D%5Cfrac%7B219.45%7D%7B8.7914%7D%20%5C%5C%5C%5Cm_1%3D24.9%5C%5C%5C%5C%20%5Capprox25%20%5Ctexttt%20%7Bgrams%7D)
<h3>25.0 grams is the mass of the steel bar.</h3>