Hamaker constant of Au is 45.5*10-20 J
Hamaker constant of SiO2 is 6.6*10-20 J
Actually hamaker value depend on different medium. For other solution than water hamaker value will be different.
2. Provide typical values of the Hamaker constant for Au and SiO2 nanospheres immersed in water. [2 marks] 2. Provide typical values of the Hamaker constant for Au and SiO2 nanospheres immersed...
what mass of water (in grams) is necessary to convert 225 g SiF4 to SiO2? SiF4 + 2 H2O → 4HF + SIO2
Which of the following will be electrolytes in water: Zn3(PO4)2, SiO2, NaBr, CaCl2, CH3COCH3
Arigidtankofvolume0.5m3isconnectedtoapiston–cylinderassemblybyavalve,asshown below. Both vessels contain pure water. They are immersed in a constant-temperature bath at 200oC and 600 kPa. Consider the tank and the piston–cylinder assembly as the system and the constant temperature bath as the surroundings. Initially the valve is closed and both units are in equilibrium with the surroundings (the bath). The rigid tank contains saturated water with a quality of 95% (i.e., 95% of the mass of water is vapor). The piston–cylinder assembly initially has a volume...
Question 9 [13 marks] A file called tanks.dat consists of the width, height and depth values for a number of water tanks. The values are all floating point and the units are metres. A typical file is shown below: 10 2.0 2.0 1.0 3.0 0.5 1.5 1.0 2.5 0.5 1.0 1.0 0.25 0.5 0.25 0.25 5.0 1.2 1.3 2.5 1.1 0.6 0.8 0.8 0.8 0.7 0.7 0.6 0.5 0.3 0.2 The first row of the file contains the number of...
QUESTION 1 (15 MARKS) a) Given 4'{+93}=LC }-( - siu (au) sin’au) sin(2t - 2u) du. Use the convolution theorem to determine the value of constant a. (5 marks) b) Using Laplace transform, solve the simultaneous differential equations dac dt - 4 =1+t, +2=t-1. dt given that x(0) = 0 and y(0) = 3. (10 marks)
1. A very smooth flat plate of length L-1 m and width b 3 m is immersed parallel to a stream of velocity 2 m/s. For both air and water as the working fluids [5 marks] Show that the flow is completely laminar over the entire plate. a. b. Determine the drag force on one side of the plate. Determine the thicknesses δ, δ*, and θ at the end of the plate (x L). [6 marks] C. For air use,...
A general Physics Question regarding Buoyant Force. If a block of 5kg mass is immersed in water attached to a spring of K constant of 500Kg in position 1, and the Buoyant force pushes the block to a certain high H which will be position 2, so the spring is now stretched, how could the change in H be found? lo a) Given Pyes bad r21 Fino Ah. lo a) Given Pyes bad r21 Fino Ah.
Q3 [30 Marks] Water (p=1000 kg/m) is flowing through a tube with the constant surface area as shown in the Figure Q3. 150 kPa 400 kPa 2 20 m 45° 1 Figure Q3 i. Calculate the diameter, if the friction factor of the pipe, the allowed velocity and the length of transport of the water are 0.025, 1.5 m/s and 200 m respectively. [15 Marks] What will happen for the system, if the friction factor of the pipe increases to...
i need 2 and 3 solved (1) A typical mud is 70 wt% sand, balance water. What is its density near RT if Puand = 2300 kg/mº? (2) An open-ended can 0.2 m tall is originally full of air, at 20°C. It is now immersed in water upside down, such that its top (now bottom) is 10 m below the water surface. The can is 0.2 m in height. Assuming the air stays at 20°C, how high will the water...
2. [20 marks] Fresh water from rivers and lakes varies in acidity/alkalinity depending on the rocks and soils it runs over. Granite country yields water that is slightly acidic, while water from limestone country is slightly alkaline. Acidity and alkalinity are measured on a pH scale, on which 7 is neutral, values below 7 are acidic and values above 7 are alkaline. pH can change due to pollution or due to waste from biomass such as algae. A certain river,...