The enthalpy of a reaction can be measured using a

The enthalpy of a reaction can be measured using a Calorimeter.

Calorimetry--

It is a science or an act that is related to measuring the enthalpy change in a reaction i.e. it is used to measure the heat changes in a chemical reaction or physical changes.

The object or the apparatus that could be used for calomitery is known as a calorimeter.

Nowadays several scanning calorimeters are also used.

         Hence, the answer is:

               Calorimeter

2.2°  

step-by-step explanation:

let θ = the angle of elevation.

tanθ =77/2020

tanθ = 0.038 12

      θ = tan⁻¹0.038 12

      θ = 2.2°

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;