is the element you mentioned before toxic?
Yes, and in cases fatal.
Thallium
Thallium and its compounds are extremely toxic, with numerous recorded cases of fatal thallium poisoning.
what is thallium? A chemical element. what are its characteristics? A thallium atom has 81 electrons arranged in the configuration [Xe]4f5d6s6p. It is malleable and sectile enough o be cut with a knife at room temperature. It has a metallic luster. how many isotopes does it have? 41. how is it produced? It is obtained as a by-product of smelting of copper, zinc, and lead ores. is it used in medicines? It is used for stress tests for risk stratification in patients with coronary artery disease. what are the symptoms of the disease that you just mentioned? Angina, shortness of breath, sweating , nausea or vomiting and lightheadedness. can the element you mentioned before be used in electronics? Yes, it is used in photoresistors. what are these? A passive component that decreases resistance with respect to receiving luminosity on the component's sensitive surface..
wiki:19618790
Thallium [SEP] Toxicity
Thallium and its compounds are extremely toxic, with numerous recorded cases of fatal thallium poisoning. The Occupational Safety and Health Administration (OSHA) has set the legal limit (permissible exposure limit) for thallium exposure in the workplace as 0.1 mg/m skin exposure over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) also set a recommended exposure limit (REL) of 0.1 mg/m skin exposure over an 8-hour workday. At levels of 15 mg/m, thallium is immediately dangerous to life and health. Contact with skin is dangerous, and adequate ventilation should be provided when melting this metal. Thallium(I) compounds have a high aqueous solubility and are readily absorbed through the skin.