A dispenser (10) for dispensing flowable materials has a container (12) having an outer wall (20), a dividing wall (21) and a membrane (14) operably connected to define a first chamber (22), a second chamber (24) and a third chamber (16). The dividing wall (21) is connected to the membrane (14) at an interface (30). The first chamber (22) defines a first volume and is configured to contain a first flowable material (M1), and the second chamber (24) defines a second volume and is configured to contain a second flowable material (M2). The membrane (14) has a first section (34) having a first rupturable member (40) and a second section (36) having a second rupturable member (40). The first section (34) is separated from the second section (36) by the interface (30). The third chamber (16) is positioned adjacent the membrane (14) generally opposite the first chamber (22) and the second chamber (24), wherein the third chamber (16) defines a third volume and is configured to receive the first flowable material (M1) and the second flowable material (M2) upon rupture of the first rupturable member (40) and the second rupturable member (40) wherein a mixture (MX) is formed. The first volume and the second volume are collectively approximately equal to the third volume.