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What types of intermolecular forces exist between NH3 and H2O?

What is the molal concentration of potassium bromide in a solution prepared by dissolving 2.27 g of potassium bromide in 897 g of water?

What is the molal concentration of a benzene (C6H6) solution prepared by mixing 13.0 g benzene with 38.0 g of carbon tetrachloride?

The solubility of oxygen gas in water at 25 °C and 1.0 atm pressure of oxygen is 0.041 g/L.  The solubility of oxygen in water at 4.0 atm and 25 °C is ________ g/L.

Answer the following questions about a solution made by dissolving 13.0 g of an unknown non-electrolyte substance in 117 g water at 20°C. Write all answers in decimal format and pay attention to significant figures (don’t include units)!   If the osmotic pressure of this solution was found to be 7.32 atm, what is the concentration of this solution (in M)? [molarity]   If the density of the solution is 1.04 g/mL, what is the volume of solution (in mL)? [volume]   How many moles of solute are present in the solution? [moles]   What is the molar mass of the solute (in g/mol)? [MM]      

Which one of the following substances would be the most soluble in CCl4?

Country A has export sales of $15 billion, government purchases of $1,100 billion, business investment is $50 billion, imports are $30 billion, and consumption spending is $2,000 billion. What is the dollar value of GDP (in billions of dollars)? 

Simulate data with sample size 500 from an ARMA(1,2) process:

The data example_wp_log_peyton_manning.csv is the data of the log daily page views for the Wikipedia pagefor Peyton Manning. Explore the data with basic summaries, time series plot and ACF plot and answer the below questions in the text box: (1) What is the sample size of this data? (2) Do you observe a general trend? Briefly describe the trend (positive/negative linear; positive then negative curve; etc.) (3) Do you observe seasonality? Give one seasonal period m you have observed. 

For the given data below, calculate a classical decomposition manually with period=3, center=False, model=multiplicative. Take two decimal places for the calculation of each step.   In the text box, provide the estimated trend, detrend data, seasonality and noises for time t=0,1,2,3,4,5. You can use Python as a simple calculator, but you can not call results from the `seasonal_decompose` function directly.