{"id":84683,"date":"2026-04-06T13:19:57","date_gmt":"2026-04-06T11:19:57","guid":{"rendered":"https:\/\/medqmedicalsuppliers.co.za\/?post_type=product&#038;p=84683"},"modified":"2026-04-06T13:20:33","modified_gmt":"2026-04-06T11:20:33","slug":"watch-glasses","status":"publish","type":"product","link":"https:\/\/medqmedicalsuppliers.co.za\/?product=watch-glasses","title":{"rendered":"Watch Glasses"},"content":{"rendered":"<p>Watch Glasses \u2013 A watch glass is a circular concave piece of glass used in chemistry as a surface to evaporate a liquid, to hold solids while being weighed, for heating a small amount of substance and as a cover for a beaker.<\/p>\n<p>Types of watch glasses<\/p>\n<ul>\n<li>Glass watch glasses \u2013 This can be reused after it is sterilized in an autoclave or a laboratory oven. The glasses made provide high resistance to thermal shock, chemical resistance and withstand mechanical durability.<\/li>\n<li>Plastic watch glasses \u2013 These are disposable watch-glass used in laboratory work to avoid any cross-contamination while preparing the samples. They are very good at implementing in low-temperatures and have an operating span of \u221257 to 135 \u00b0C it can also resist UV light degradation. These plastic watch glasses are less expensive and light in weight<\/li>\n<\/ul>\n<p>Uses of watch glasses<\/p>\n<ul>\n<li>One of the generic uses of a watch glass as mentioned previously includes as a lid for beakers. In this case a watch glass is placed above the container, which makes it easier to control and alter vapour saturation conditions.<\/li>\n<li>A watch glass is often used to house solids being weighed on the scale. Prior to weighing desired amount of solid, a watch glass is placed on the scale, followed by taring or zeroing the scale so that only the weight of the sample substance is obtained.<\/li>\n<li>Watch glass can also be used for drying solids. When further drying is required, a watch glass is often used in cases where a particular type of solid needs to be separated from its comparatively volatile solvent. The solid is spread on a watch glass and, often time, a folded filter paper is placed above to keep out airborne particles from contaminating the product. <\/li>\n<li>To maximize the drying rate, a watch glass can be placed inside a fume hood to provide good air circulation for an adequate amount of time. Another technique used in chemistry laboratories to increase the drying rate is passing a gentle stream of dry air or nitrogen gas over the watch glass from an inverted funnel clamped above it.<\/li>\n<\/ul>\n<p>Add to Wishlist<\/p>\n<p> Add to Wishlist<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Watch Glasses<\/p>\n","protected":false},"featured_media":84751,"template":"","meta":{"content-type":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}}},"product_brand":[],"product_cat":[40289],"product_tag":[25671],"class_list":["post-84683","product","type-product","status-publish","has-post-thumbnail","product_cat-glass-miscellaneous-other-disposable-consumables-items","product_tag-watch-glasses","desktop-align-center","tablet-align-center","mobile-align-center","first","instock","shipping-taxable","purchasable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=\/wp\/v2\/product\/84683","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=\/wp\/v2\/product"}],"about":[{"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=\/wp\/v2\/media\/84751"}],"wp:attachment":[{"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=84683"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=%2Fwp%2Fv2%2Fproduct_brand&post=84683"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=%2Fwp%2Fv2%2Fproduct_cat&post=84683"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/medqmedicalsuppliers.co.za\/index.php?rest_route=%2Fwp%2Fv2%2Fproduct_tag&post=84683"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}