Virtual lab refers to a virtual teaching and learning environment aimed at developing students' laboratory skills. As one of the most important eLearning tools, they allow the student to conduct various experiments without any constraints to place or time, in contrast to the constraints of real labs.

As one of the most important eLearning tools, they allow the student to conduct various experiments without any constraints to place or time, in contrast to the constraints of real labs. Virtual labs incorporate various pedagogical techniques that help learners to better understand the theoretical information.

5 Disadvantages of Virtual Laboratory They require computer devices with high specifications in order to simulate the exact phenomena with full details and create a three-dimensional virtual lab. They require professional programmers with strong skills in different programming languages.

This meta-analysis offered information on the effectiveness of using virtual laboratory activities to student achievement. Results of the meta-analysis revealed a medium effect size (g = 0.587) towards the use of virtual laboratories.

Moreover, virtual labs make possible experiments than would otherwise be too dangerous, such as studying the functions of a nuclear reactor. However, virtual labs have become under criticism from their lack of real-life feel and not teaching about health and safety to students.

The Virtual Labs can be accessed anytime and anywhere, overcoming the constraints of time as physical labs are available only during school hours.

When handling these materials, personal protective equipment such as gloves, laboratory coats, masks, goggles should be worn to prevent any contamination to the samples and to the experimenter.

A virtual laboratory is also useful in providing opportunities for students to learn by doing, developing thinking skills, and problem-solving skills [6]. In another study, the use of project-based learning model that is supported by virtual media can improve students' creativity [7].

9 Benefits of Virtual Labs Virtual labs motivate students to conduct laboratory experiments. They satisfy the scientific passion of students, allowing them to access the various experiments easily regardless of time or place.