Which of the following statements regarding carbon dioxide is/are correct? 1. It is prepared on large scale by the action of water on lime. 2. In the solid form it can be used as a refrigerant. Select the correct answer using the code given below :

Statement 1 is incorrect because the action of water on lime (calcium oxide) produces calcium hydroxide (slaked lime) and heat, not carbon dioxide [c5, t2, t5]. In fact, carbon dioxide is a byproduct of the reverse process—the thermal decomposition or calcination of limestone (calcium carbonate) to produce lime [t6, t7]. On a large industrial scale, carbon dioxide is often captured from such calcination processes or ammonia production [t4, t6]. Statement 2 is correct as solid carbon dioxide, commonly known as dry ice, is widely used as a refrigerant [t1]. It is preferred because it sublimes directly into gas without leaving a liquid residue, providing a cooling effect approximately twice that of water ice at certain temperatures [t1, t3]. Therefore, only the second statement is accurate regarding the properties and production of carbon dioxide.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > Figure 1.3 > p. 6
2. [2] https://www.govinfo.gov/content/pkg/GOVPUB-C13-96a90b7ce08fbc3a2833740fdda09ddf/pdf/GOVPUB-C13-96a90b7ce08fbc3a2833740fdda09ddf.pdf
3. [3] https://www.ams.usda.gov/sites/default/files/media/2023TechnicalReportHandlingCalciumHydroxide.pdf
4. [4] https://19january2017snapshot.epa.gov/sites/production/files/2015-12/documents/us-ghg-inventory-2015-chapter-4-industrial-processes.pdf
5. [5] https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=9100SNS0.TXT
6. [6] https://etheses.whiterose.ac.uk/id/eprint/31832/1/Thesis_Marco%20Simoni.pdf